自定义控件

点击Button，EditText里的字会清空

MainActivity:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <com.example.canvastest.MyView
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

</LinearLayout>

public class MainActivity extends Activity {
    public static final String TAG = "MainActivity";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

MyView:

<?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" >

    <EditText
        android:id="@+id/edt"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <Button
        android:id="@+id/btn"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="clear" />

</LinearLayout>

public class MyView extends LinearLayout implements View.OnClickListener {
    private EditText edt;
    private Button btn;

    public MyView(Context context, AttributeSet attrs) {
        super(context, attrs);

        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View view = inflater.inflate(R.layout.myview, this);

        edt = (EditText) view.findViewById(R.id.edt);

        btn = (Button) view.findViewById(R.id.btn);
        btn.setOnClickListener(this);
    }

    @Override
    public void onDraw(Canvas canvas) {
        super.onDraw(canvas);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.btn:
            edt.setText("");
            break;
        }
    }
}