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POHow to inflate XML-Layout-File correctly inside Custom ViewGroup?
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  1. POHow to inflate XML-Layout-File correctly inside Custom ViewGroup?
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    copied!<p>I want to inflate a XML-Layout-File in a custom ViewGroup Class, my Problem is that it produces just a empty screen. Doing the same in the Activity Class works fine. Here is my simple XML-Layout-File: </p> <pre><code>shownumberlayout.xml: &lt;RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:background="#FFFFFF" android:id="@+id/layoutForNumber"&gt; &lt;TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/tvNumber" android:layout_centerHorizontal="true" android:textColor="#000000" android:text="Test" android:layout_centerVertical="true" android:textSize="30dip"&gt; &lt;/TextView&gt; &lt;/RelativeLayout&gt; </code></pre> <p>Here is the working Version, inflating the <code>shownumberlayout.xml</code> in the Activity <code>ShowNumber</code>:</p> <pre><code>ShowNumber.class public class ShowNumber extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE); ViewGroup vg = (ViewGroup) inflater.inflate(R.layout.shownumberlayout, null); setContentView(vg); } } </code></pre> <p>This shows a White Background with the black Text “Test” centered.</p> <p>Now the Version inflating the xml in the Custom <code>ViewGroup</code>-Class:</p> <pre><code>ViewGroup.class public class ViewNumber extends ViewGroup { private LayoutInflater inflater; public ViewNumber(Context context) { super(context); // TODO Auto-generated constructor stub initView(context); } public ViewNumber(Context context, AttributeSet attrs) { super(context, attrs); // TODO Auto-generated constructor stub initView(context); } public ViewNumber(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // TODO Auto-generated constructor stub initView(context); } private void initView(Context context){ inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); inflater.inflate(R.layout.shownumberlayout, null); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { // TODO Auto-generated method stub } } </code></pre> <p>ShowNumber.class public class ShowNumber extends Activity { /** Called when the activity is first created. */</p> <pre><code>@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); ViewGroup vg = new ViewNumber(this); setContentView(vg); } </code></pre> <p>}</p> <p>Im doing it basically like in <a href="https://stackoverflow.com/questions/3368182/anyway-to-use-xml-layout-files-for-specific-view-viewgroups">this</a> Answer explained. This just produces a Empty Black Screen. What I am doing wrong?</p> <p><strong>UPDATE 1</strong></p> <p><strong>@Konstantin</strong> I applied your changes but still just a blank screen, i also made a log-ouput for getting the number of children. It remains always 1, even i add one more Textview to the XML-Layout-File. Before the Changes it remains always 0.</p> <pre><code>public class ViewNumber extends RelativeLayout { ... private void initView(Context context){ //inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); //inflater.inflate(R.layout.shownumberlayout, null); View.inflate(context, R.layout.shownumberlayout,this); Log.v("ViewNumber", "Number of Child: " + this.getChildCount());//output is 1,before it remains 0 } ... } </code></pre> <p><strong>@Sankar</strong> This is the Logcat, after the Changes from Konstantin:</p> <pre><code>12-16 09:24:23.606: DEBUG/AndroidRuntime(8951): &gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt; AndroidRuntime START &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; 12-16 09:24:23.606: DEBUG/AndroidRuntime(8951): CheckJNI is OFF 12-16 09:24:23.606: DEBUG/dalvikvm(8951): creating instr width table 12-16 09:24:23.656: DEBUG/AndroidRuntime(8951): --- registering native functions --- 12-16 09:24:23.916: DEBUG/AndroidRuntime(8951): Shutting down VM 12-16 09:24:23.916: DEBUG/dalvikvm(8951): Debugger has detached; object registry had 1 entries 12-16 09:24:23.916: INFO/AndroidRuntime(8951): NOTE: attach of thread 'Binder Thread #3' failed 12-16 09:24:24.076: DEBUG/AndroidRuntime(8960): &gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt;&gt; AndroidRuntime START &lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt;&lt; 12-16 09:24:24.076: DEBUG/AndroidRuntime(8960): CheckJNI is OFF 12-16 09:24:24.076: DEBUG/dalvikvm(8960): creating instr width table 12-16 09:24:24.126: DEBUG/AndroidRuntime(8960): --- registering native functions --- 12-16 09:24:24.376: INFO/ActivityManager(78): Starting activity: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=org.customview.harold/.ShowNumber } 12-16 09:24:24.426: DEBUG/AndroidRuntime(8960): Shutting down VM 12-16 09:24:24.426: DEBUG/jdwp(8960): Got wake-up signal, bailing out of select 12-16 09:24:24.426: DEBUG/dalvikvm(8960): Debugger has detached; object registry had 1 entries 12-16 09:24:24.456: INFO/AndroidRuntime(8960): NOTE: attach of thread 'Binder Thread #3' failed 12-16 09:24:24.456: VERBOSE/ViewNumber(8923): Number of Child: 1 12-16 09:24:24.496: VERBOSE/RenderScript_jni(164): surfaceDestroyed 12-16 09:24:24.526: INFO/ActivityManager(78): Displayed activity org.customview.harold/.ShowNumber: 104 ms (total 104 ms) 12-16 09:24:24.576: DEBUG/dalvikvm(158): GC_FOR_MALLOC freed 10631 objects / 526248 bytes in 52ms 12-16 09:24:34.606: DEBUG/dalvikvm(164): GC_EXPLICIT freed 1776 objects / 106960 bytes in 91ms </code></pre> <p><strong>UPDATE 2</strong></p> <p>The Content is finally showing correctly up. The missing thing was to override the Method <code>onLayout</code> (thanks to <strong>Franco</strong>) in the RelativeLayout-Sublcass:</p> <pre><code>public class ViewNumber extends RelativeLayout { ... @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { // TODO Auto-generated method stub for(int i = 0 ; i &lt; getChildCount() ; i++){ getChildAt(i).layout(l, t, r, b); } } ... } </code></pre> <p>Note: Later you should also override the Method <code>onMeasurement()</code>, but currently the content is also showing correctly without overriding it.</p> <p>Now the solution for the Method <code>initView</code> from <strong>Franco</strong> do not align the TextView in the Center, but puts it in the top left corner. The solution from <strong>Konstantin</strong> puts it correctly in the Center of the View:</p> <pre><code>public class ViewNumber extends RelativeLayout { ... private void initView(Context context){ View.inflate(context, R.layout.shownumberlayout,this); } ... } </code></pre>
 

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