I'm trying to make chart with reclyerview. The issue that i'm having is i can't seem to make child items align from bottom, instead of the top of the reclyerview.
I have tried, reverseLayout and stackFromEnd
I have searched left and right. Still have no idea why does this happen.
Can anyone please help me.
Any helpfull ideas would be appreciated.
Layout managers align items to top-start by default because it's the most stable in case RecyclerView has height of wrap_content which could cause some layout issues.
If your RecyclerView has fixed size you can try to extend layout manager you're using to force it to lay out items on bottom:
// inside your activity or fragment where you're initializing RecyclerView
recyclerView.setLayoutManager(new LinearLayoutManager(context, LinearLayoutManager.HORIZONTAL, false) {
#Override
public void layoutDecoratedWithMargins(#NonNull View child, int left, int top, int right, int bottom) {
// calculate available space in recyclerView
int offset = getHeight() - getPaddingTop() - getPaddingBottom();
// subtract height of item being laid out
offset -= bottom - top;
// lay out item lower than usual
super.layoutDecoratedWithMargins(child, left, top + offset, right, bottom + offset);
}
});
I kinda figured it out.
As i have static height, i created another wrapper around child, that was alligned to bottom, and the parrent set as specific height.
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="80dp"
android:layout_height="200dp"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:layout_marginRight="8dp"
>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent">
<TextView
android:id="#+id/tv_time"
style="#style/BoldWhiteText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="7.5"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
Related
Just trying to center my RecyclerView horizontal.
Here is the xml:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</RelativeLayout>
And here the java code:
mRecyclerView = findViewById(R.id.recycler_view);
itemLayoutManager = new GridLayoutManager(this, 6);
mRecyclerView.setLayoutManager(itemLayoutManager);
...
mItemAdapter = new ItemAdapter(MainActivity.this, mItemList);
mRecyclerView.setAdapter(mItemAdapter);
When I run the application the recyclerview aligns left.
What exactly do I have to do to center the content so that the margin is the same left and right like in the example picture on the right side?
Create a class like to set paddings to item:
class SpacingItemDecorator (private val padding: Int) : RecyclerView.ItemDecoration()
{
override fun getItemOffsets(
outRect: Rect,
view: View,
parent: RecyclerView,
state: RecyclerView.State
)
{
super.getItemOffsets(outRect, view, parent, state)
outRect.top = padding
outRect.bottom = padding
outRect.left = padding
outRect.right = padding
}
}
Now in Your RecyclerView set paddingStart and paddingEnd, e.g 4dp :
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingStart="4dp"
android:paddingEnd="4dp"
app:layoutManager="androidx.recyclerview.widget.GridLayoutManager"
app:spanCount="6"/>
When You create adapter just apply this item decorator:
val x = (resources.displayMetrics.density * 4).toInt() //converting dp to pixels
recyclerView.addItemDecoration(SpacingItemDecorator(x)) //setting space between items in RecyclerView
RecyclerView item:
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardCornerRadius="6dp"
app:cardElevation="4dp">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:id="#+id/txtContent"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#{Integer.toString(dataView.id)}"
android:textSize="20sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"/>
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
Result:
I faced the same issue recently and looked into the source code. There's no straight forward way to do this using GridLayoutManager. The other was is to use a GridView which is more customisable.
This is an alternate solution for you or any one else looking for a workaround.
I didn't want to change to a GridView so this is what I did. I set the RecyclerView's layout width to wrap_content and centered it horizontally within the parent (which in your case is a RelativeLayout so it will be something like android:centerHorizontally="true")
I knew the item width so I calculated the spanCount by dividing the screen width by the item width (plus any horizontal margins). Now I set the span count to the grid layout manager and it gets centered horizontally just how you want it.
Adding margins to you item's layout root play an important role here.
I'm writing a code for a school project where one has to load a data file (CSV file, text file, etc) and from the obtained data, the app will pass the data to a custom draw View and the onDraw method will draw/plot a graph based on the data.
My goal is for the app to display 2 graphs, one after the other (stacked). The first set of data is loaded and the 1st graph is drawn. The loaded data is then used for a different calculation in a different method. The custom draw View is then called again with the new data to draw the 2nd graph.
When I run the app, both charts are drawn but because the x and y-axis' of the graph are coded to be drawn at certain fixed pixels, the 2nd graph is drawn over the first one and therefore only the 2nd graph is visible.
Is there any way I can draw the 2 graphs so that it does not overlap and instead appears to be stacked in ScrollView?
My code is shown below but I've gotten rid of calculations that I think aren't very important. Any help and pointers would be very much appreciated!
MainActivity.java:
#Override
protected void onActivityResult(......) {
super.onActivityResult(......);
switch (1) {
case 1:
Graph graph = this.findViewById(R.id.graph1);
graph.setData(data); // the loaded data is passed to Graph View
Graph drawGraph2 = this.findViewById(R.id.graph2);
graph2.setData(this.newCalculate(data));
break;
}
}
Graph.java
public class Graph extends View {
private Paint mPaint = new Paint();
private final int zero = 700; // mark the 0 line of graph at 700 pixels
public void setData(data){
......
}
public Graph(Context context, AttributeSet attributeSet) {
super(context, attributeSet);
}
#Override
protected void onMeasure (int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
setMeasuredDimension(widthSize, heightSize);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
plotUnit(canvas); // plot points on graph
axisLabel(canvas); // label axis
axisLine(canvas); // draw axis
xyAxisMarker(canvas); // mark axis
}
private void plotUnit(Canvas canvas) {
......
// Due to data having negative values, the graph is inverted and the 0 starts
// of the graph is defined at 700 pixels （private final int zero)
}
private void axisLabel(Canvas canvas) {
......
}
private void axisLine(Canvas canvas, int inset) {
......
}
private void xyAxisMarker(Canvas canvas) {
......
}
Update
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<Button
android:id="#+id/loadbutton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Open Data File" />
<firstapp.drawtwograph.Graph
android:id="#+id/graph1"
android:layout_width="wrap_content"
android:layout_height="match_parent" />
<firstapp.drawtwograph.Graph
android:id="#+id/graph2"
android:layout_width="wrap_content"
android:layout_height="match_parent" />
</LinearLayout>
</ScrollView>
</LinearLayout>
You cannot have two views' heights match parent height inside of a LinearLayout with vertical orientation. It is not possible because heights of these views must be equal to the parent height but at the same time, they must be ordered one after the other resulting in double of parent's height.
If you imagine parent's height as 10dp then each of the Graph views must be 10dp as well which means parent's height must be 20dp, not 10dp. That is going to cycle forever so the Android does a simple thing: views that are going below the first child view with android:layout_height="match_parent" will have height 0dp or if their height is fixed they will be drawn outside of the layout and will not be visible.
Example
Screenshot from Design tab of layout editor in Android Studio IDE.
Here you can see:
red view as a parent linear layout;
purple view as a first child with height matching it's parent height;
outlined view that is drawn outside of the layout because it is pushed out by the first child with android:layout_height="match_parent";
there is one more view that is crushed to 0 height and thus not visible. You can see it down in the XML code.
XML code of this sample:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="100dp"
android:background="#android:color/holo_red_light">
<LinearLayout
android:background="#color/colorPrimary"
android:layout_width="60dp"
android:layout_height="match_parent" <!-- this view's height is a problem -->
android:orientation="vertical"/>
<LinearLayout
android:background="#android:color/holo_green_dark"
android:layout_width="120dp"
android:layout_height="match_parent" <!-- height is not fixed, then it will be 0 -->
android:orientation="vertical"/>
<LinearLayout
android:background="#android:color/holo_green_light"
android:layout_width="120dp"
android:layout_height="40dp" <!-- height is fixed, it is outlined outside of a layout -->
android:orientation="vertical"/>
</LinearLayout>
How to fix the issue?
Set fixed height. As a test try to define a fixed height, e.g. 100dp;
Redesign your layout. Use RelativeLayout or ConstraintLayout to position views relative to each other so that they are always visible no matter what the screen size, ratio, density is.
Example of how to fix
I personally prefer ConstraintLayout as it is very powerful in terms of positioning and adaptation.
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<Button
android:id="#+id/loadbutton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Open Data File"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<firstapp.drawtwograph.Graph
android:id="#+id/graph1"
android:layout_width="wrap_content"
android:layout_height="0dp"
app:layout_constraintBottom_toTopOf="#+id/graph2"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/loadbutton" />
<firstapp.drawtwograph.Graph
android:id="#+id/graph2"
android:layout_width="wrap_content"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/graph1" />
</androidx.constraintlayout.widget.ConstraintLayout>
The result is (I used two buttons instead of Graph views):
Hints:
If you want to use ScrollView then setting fixed height or defining height at runtime will be required.
Get rid of private final int zero = 700; // mark the 0 line of graph at 700 pixels. Do not use pixel values directly as it will lead to error-prone UI. It will be the case of "work on my phone, does not work the other". Use view's height as the 0 line.
I have a custom ConstraintLayout class (Card.java) which overrides the onDraw() method to draw a hexagon in his background. On the foreground i try to have three TextViews to display three numbers.
For this I inflate a card.xml in the constructor of Card. The TextViews are displayed, but not at the right position. They should match the width and height of the Card and then position itself to the top-left and top-right corner and one to the bottom of the Card. But they do something like shrink itself and go to the top-left corner.
I have tried to change the root element of card.xml to "merge" instead of "...ConstraintLayout" but this doesn't change anything.
I also tried to use Guidelines to position the TextViews relative to its width. I try to prevent the use of fixed margins, so the Text is always at the right place, also when the size of the Card changes.
Card.java:
public class Card extends ConstraintLayout {
private int mSize;
private Path mHexagon;
private Paint mPaintHexagon;
private TextView mT1, mT2, mT3;
public Card(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
inflate(context, R.layout.card, this);
// Numbers
mT1 = findViewById(R.id.num1);
mT2 = findViewById(R.id.num2);
mT3 = findViewById(R.id.num3);
// Hexagon
mSize = Field.getHexSize(); // Size is used to calculate the
setPath();
mPaintHexagon = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaintHexagon.setColor(0x50888888);
mPaintHexagon.setStyle(Paint.Style.FILL);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawPath(mHexagon, mPaintHexagon);
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int width = 2 * mSize;
int height = (int) (Math.sqrt(3) * mSize);
Log.d(TAG, "Measure w:" + width + " h:" + height);
setMeasuredDimension(width, height);
}
}
card.xml:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/num2"
android:textAppearance="#style/TextAppearance.AppCompat.Large"
android:text="2"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginTop="8dp"
app:layout_constraintStart_toStartOf="parent"
android:layout_marginStart="8dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/num1"
android:textAppearance="#style/TextAppearance.AppCompat.Large"
android:text="1"
app:layout_constraintStart_toEndOf="#+id/num2"
app:layout_constraintEnd_toStartOf="#+id/num3"
app:layout_constraintBottom_toBottomOf="parent"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/num3"
android:textAppearance="#style/TextAppearance.AppCompat.Large"
android:text="3"
app:layout_constraintEnd_toEndOf="parent"
android:layout_marginEnd="8dp"
app:layout_constraintTop_toTopOf="parent"
android:layout_marginTop="8dp"/>
</android.support.constraint.ConstraintLayout>
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity"
android:background="#color/colorAccentDark"
android:padding="5dp">
<de.portugall.markus.takeiteasy.Card
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
android:id="#+id/card"/>
</android.support.constraint.ConstraintLayout>
Screenshot Card in Layout-Debug mode
'onMeasure()` has some rules that you are not strictly following. I have seen these rules broken with impunity, but I think that you are being caught, but we will push on.
In onMeasure() you are setting the height and width of the custom layout but ConstraintLayout still understands the layout as wrap_content. You will need to set the layout params to the new height and width. Add the following code to the end of onMeasure():
// Although we have measured the layout, we need to tell ConstraintLayout in the
// LayoutParams that the size is not longer "wrap_content".
ViewGroup.LayoutParams lp = getLayoutParams();
lp.width = width;
lp.height = height;
setLayoutParams(lp);
The second issue that you have is that you are adding a ConstraintLayout (card.xml) to a ConstraintLayout (your custom layout), but you are not setting the constraints. In the constructor for Card.java, add the following to set the constraints:
ConstraintLayout layout = (ConstraintLayout) inflate(context, R.layout.card, this);
// We have added R.layout.card to a ConstraintLayout (this custom layout), so we need
// to make sure that it is constrained properly.
ConstraintSet cs = new ConstraintSet();
cs.clone(layout);
cs.connect(R.id.layout, ConstraintSet.START, ConstraintSet.PARENT_ID, ConstraintSet.START);
cs.connect(R.id.layout, ConstraintSet.TOP, ConstraintSet.PARENT_ID, ConstraintSet.TOP);
cs.connect(R.id.layout, ConstraintSet.END, ConstraintSet.PARENT_ID, ConstraintSet.END);
cs.connect(R.id.layout, ConstraintSet.BOTTOM, ConstraintSet.PARENT_ID, ConstraintSet.BOTTOM);
cs.applyTo(layout);
You will need to change the height and width of the layout in card.xml to 0dp. match_parent is never appropriate in ConstraintLayout.
This is a pictorial description of what is happening:
On a related note, you should consider using the merge facility to avoid nested ConstraintLayouts as other have mentioned.
I am creating a HorizontalScrollView in xml and inserting the images programmatically, but I am having trouble with margins. How do I set the horizontal margins for images in the HorizontalScrollView? Below is my code:
xml:
<HorizontalScrollView
android:id="#+id/HorizontalScrollView"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_centerHorizontal="true"
android:layout_marginBottom="15dp">
<LinearLayout
android:id="#+id/innerLay"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<!--Image Views here -->
</LinearLayout>
</HorizontalScrollView>
java:
ImageView imageView = new ImageView(getActivity());
scrollLinearLayout.addView(imageView);
//set height and other image properties.
Use this function to set runtime margin to view
public static void setMargins (View v, int left, int top, int right, int bottom) {
if (v.getLayoutParams() instanceof ViewGroup.MarginLayoutParams) {
ViewGroup.MarginLayoutParams p = (ViewGroup.MarginLayoutParams) v.getLayoutParams();
p.setMargins(left, top, right, bottom);
v.requestLayout();
}
}
I am trying to center a view within a parent RelativeLayout:
private void addLoadingAnimation() {
RelativeLayout mainView = (RelativeLayout) findViewById(R.id.medical_supply_tile_activity);
mainView.removeAllViews();
GifView gifView = new GifView(this);
RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
layoutParams.addRule(RelativeLayout.CENTER_IN_PARENT);
gifView.setId(R.id.loading_gif);
mainView.setBackgroundColor(getResources().getColor(android.R.color.background_light));
mainView.addView(gifView,layoutParams);
}
I have also tried adding layoutParams.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, 0); before the CENTER_IN_PARENT line. Nothing seems to be working. It is always aligned to the bottom right.
Here is my parent view:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#android:color/background_light"
tools:context=".MedecineTileActivity"
android:id="#id/medical_supply_tile_activity"
android:layout_gravity="left">
</RelativeLayout>
The gravity=left is because when the loading animation is removed, I insert fragments and want them to go to the left.
I have achieved this with TextViews and ImageViews by aligning the child View's right to the parent's right and also aligning the child View's left to the parent's left.
<TextView
style="#style/NewTextM2"
android:id="#+id/soft_dialog_info_item_text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/<Parent>"
android:layout_alignLeft="#+id/<Parent>"
android:layout_alignRight="#+id/<Parent>"
android:gravity="center"
android:tag="item_text"
android:text="#string/text"
android:maxLines="1" />
This will align the view to the bottom center of the parent.