The problem is:
1st you should declare instance of view in GameActivity.java
2nd remove setContentView(R.layout.activity_game);.
MainActivity.java
public class TitleActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_title);
Button switchButton = (Button) findViewById(R.id.button1);
switchButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(TitleActivity.this,
GameActivity.class);
startActivity(intent);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.title, menu);
return true;
}}
GameActivity.java
public class GameActivity extends Activity {
private DrawV drawView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Declare instance of DrawV ...
drawView = new DrawV(this);
// setContentView
setContentView(drawView);
}}
DrawV.java
public class DrawV extends View {
private Bitmap bit_dot;
public DrawV(Context context) {
super(context);
bit_dot = BitmapFactory.decodeResource(getResources(),
R.drawable.ic_launcher);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(bit_dot, 100, 100, null);
canvas.drawBitmap(bit_dot, 50, 50, null);
}}
activity_title.xml
<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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".TitleActivity" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="41dp"
android:layout_marginTop="52dp"
android:text="Button" />
</RelativeLayout>
acticity_game.xml
<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=".GameActivity"
>
<View
class="com.category.tap.DrawV"
android:layout_width="100dp"
android:layout_height="100dp" />
</RelativeLayout>