Develop Reference

Is there a way in android to set a field via xml android:id into a custom view

For instance I have a custom button and want to connect it to a SeekBar:
public class SeekBarButton extends ImageButton {
SeekBar seekBar;
public SeekBarButton(Context context) {
super(context);
}
public SeekBarButton(Context context, AttributeSet attrs) {
super(context, attrs);
}
public SeekBarButton(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
public void setSeekBar(SeekBar seekBar) {
this.seekBar = seekBar;
}
public SeekBar getSeekBar() {
return seekBar;
}
}
I can do it in the code:
sbb = (SeekBarButton) rootView.findViewById(R.id.minus_red);
sbRed = (SeekBar) rootView.findViewById(R.id.sbRed);
sbb.setSeekBar(sbRed);
But 8 buttons will give a lot of boilerplate, and I want something like:
<com.whatever.views.SeekBarButton
...
whatToPutHere:seekbar="#+id/sbRed" // like this? whatToPutHere?
android:id="#+id/minus_red" />
<SeekBar
android:id="#+id/sbRed"
... />

The easiest way to do this is to create a custom ViewGroup that contains both the Button and Seekbar. If you cannot do that, for any reason, here's a solution:
There are a few steps to make this work. First you must define a custom XML attribute that you can then reference and use.
Edit (or create) res/values/attrs.xml. Add:
<declare-styleable name="SeekBarButton">
<attr name="seekbarId" format="integer" />
</declare-styleable>
Then, in SeekBarButton, call this from the constructors:
private void init(Context context, AttributeSet attrs, int defStyleAttr) {
if (attrs != null) {
TypedArray a = context.obtainStyledAttributes(attrs,
R.styleable.SeekBarButton, defStyleAttr, 0);
mSeekbarId = a.getResourceId(R.styleable.SeekBarButton_seekbarId, 0);
a.recycle();
}
}
Finally, in your root ViewGroup of your layout file, add
xmlns:app="http://schemas.android.com/apk/res-auto"
Then,
<com.whatever.views.SeekBarButton
android:id="#+id/minus_red"
app:seekbarId="#+id/sbRed"
... />
<SeekBar
android:id="#+id/sbRed"
... />
Note You will need to call ((ViewGroup) getParent()).findViewById(mSeekbarId) in SeekBarButton to instantiate the SeekBar, but getParent() will be null in SeekBarButton constructors. So, delay findViewById() until you need the SeekBar.

I think you are close. In the first XML tag of your layout file (my example is a RelativeLayout) you need this reference to "custom":
<RelativeLayout
xmlns:custom="http://schemas.android.com/apk/res-auto">
Then farther down wherever your custom ImageButton is, you need this:
<com.whatever.views.SeekBarButton
...
custom:seekbar="#+id/sbRed"
android:id="#+id/minus_red" />
You will also need a seekBarButton.xml file in your project\res\values folder, if you didn't already know that.

android.view.InflateException Error inflating class com.etsy.android.grid.StaggeredGridView

I am implementing the library provided by etsy on github for StaggeredGrid https://github.com/etsy/AndroidStaggeredGrid . The error i am getting is InflationException for the layout activity_svg.xml
<com.etsy.android.grid.StaggeredGridView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/grid_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:item_margin="8dp"
app:column_count="#integer/grid_column_count" />
android.view.InflationException Binary XML File Line#3 Error inflating class com.etsy.android.grid.StaggeredGridView
As per previous answers related to the question i have checked the constructors :
public StaggeredGridView(final Context context) {
this(context, null);
}
public StaggeredGridView(final Context context, final AttributeSet attrs) {
this(context, attrs, 0);
}
public StaggeredGridView(final Context context, final AttributeSet attrs, final int defStyle) {
super(context, attrs, defStyle);
As per previous answer i have also checked whether the file lies in this library or not.
So what else can be the problem for InflationException ? Why is the class not getting inflated?
If you want me to add any more part of the code please comment.

If you have custom controls in your application then it should be specified using the full package in your layout XML, if only "yourcustomcontrol" is used it will throw this error. For example:
<yourcustomcontrol android:id="#+id/yourCustomControl1" /> will throw error.
<packageName.yourcustomcontrol android:id="#+id/yourCustomControl1" />
will work.
More about custom controls can be found at the android developers' homepage here
Originally answered here.

Gridview show according to actual height within scroll view

<ScrollView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/titleBarBG"
android:layout_alignParentLeft="true" >
<RelativeLayout
android:id="#+id/scrollContent"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<GridView
android:id="#+id/issueList"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/archiveTitle"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:background="#drawable/customshape"
android:numColumns="3"
android:overScrollMode="never"
android:scrollbars="none" >
</GridView>
</RelativeLayout>
</ScrollView>
I would like to create a gridview that act like a table . For example, the size of the grid will increase that will make the gridview taller. Instead of hide the extra content ,I would like the grid view show all content and expand the height when there is additional content
How to implement this? thanks

public class MyGridView extends GridView {
public MyGridView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MyGridView(Context context) {
super(context);
}
public MyGridView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
#Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec);
}
}

This is slightly cleaned up version of: Grid of images inside ScrollView
WrappedGridView.java:
/**
* Use this class when you want a gridview that doesn't scroll and automatically
* wraps to the height of its contents
*/
public class WrappedGridView extends GridView {
public WrappedGridView(Context context) {
super(context);
}
public WrappedGridView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public WrappedGridView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
#Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// Calculate entire height by providing a very large height hint.
// View.MEASURED_SIZE_MASK represents the largest height possible.
int expandSpec = MeasureSpec.makeMeasureSpec(MEASURED_SIZE_MASK, MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec);
ViewGroup.LayoutParams params = getLayoutParams();
params.height = getMeasuredHeight();
}
}
Include in an XML layout like you would a GridLayout. Use an adapter to provide it views.
As far as I can tell, this is the simplest solution available now. There no other view available in the framework that handles wrapping. It would be nice if someone were to provide an elegant, automatically sizing table view. Modifying GridView.java for this purpose may not be a bad idea.
Alternatively, you may find one of the 'FlowLayout' projects acceptable. There is android-flowlayout and FlowLayout. These are a little more flexible than a simple grid and, I assume, a little less efficient. You also shouldn't need to provide them an adapter.

Rotating a RelativeLayout in Android 2.3

I am new to android and would like some assistance on rotating my relative layout for a two-player game I am working on. I have seen the posts here and have looked into many other posts on the same subject on SO. My first question is how to I call the new class I just made? For all the posts that dont just tell me to use android:rotation (which is not avaliable in 2.3-) I make a new class, but I get a notification that the class is never called. Do I call the class simmilar to how I call a method? Or is there some command in AndroidManifest? Finialy, how does the new class rotate only one Relative layout and not the other? I just would like to know how its supposted to work.
This is the new Class that I am supposted to make:
public class MyRelativeLayout extends RelativeLayout {
public MyRelativeLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
public MyRelativeLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public MyRelativeLayout(Context context) {
super(context);
init();
}
private void init() {
setStaticTransformationsEnabled(true);
}
#Override
protected boolean getChildStaticTransformation(View child, Transformation t) {
t.setTransformationType(Transformation.TYPE_MATRIX);
Matrix m = t.getMatrix();
m.reset();
m.postRotate(180, child.getWidth() / 2.0f, child.getHeight() / 2.0f);
return true;
Thanks for your help

In the oncreate() method in your activity do setContentView(new MyRelativeLayout(this))

How can I support unicode fonts in Android?

I need to show Hindi and Bengali font support in my app. How to do this.Please help.
Also tell me how can I get the support from XML, as I need to get the data through web-services.

What I did is that is put a particular font of choice to assets folder and used this code:
public class CustomTextView extends TextView{
public CustomTextView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initFont();
}
public CustomTextView(Context context, AttributeSet attrs) {
super(context, attrs);
initFont();
}
public CustomTextView(Context context) {
super(context);
initFont();
}
private void initFont() {
Typeface tf = Typeface.createFromAsset(getContext().getAssets(),"myfont.ttf");
setTypeface(tf);
}
}
But the problem what I am facing is that the even if I am getting the fonts in my emulator some of the fonts patterns are not correct.
Reply if anybody wants to add more to my answer, you are welcome.