画面布局

public class ex04 extends Activity {
private final int WC = LinearLayout.LayoutParams.WRAP_CONTENT;
@Override public void onCreate(Bundle icicle) {
super.onCreate(icicle);
LinearLayout layout = new LinearLayout(this);
layout.setOrientation(LinearLayout.VERTICAL);
ImageButton btn = new ImageButton(this);
Drawable dw = this.getResources().getDrawable(R.drawable.ok);
btn.setImageDrawable(dw); btn.setOnClickListener(listener);
LinearLayout.LayoutParams param =
new LinearLayout.LayoutParams(WC, WC);
layout.addView(btn, param);
ImageButton btn2 = new ImageButton(this);
dw = this.getResources().getDrawable(R.drawable.exit);
btn2.setImageDrawable(dw); btn2.setOnClickListener(listener2);
layout.addView(btn2, param);
LinearLayout out_layout = new LinearLayout(this);
out_layout.setOrientation(LinearLayout.HORIZONTAL);
Button btn3 = new Button(this);
btn3.setText("Cancel"); btn3.setTextColor(Color.WHITE);
btn3.setBackgroundColor(Color.RED); btn3.setOnClickListener(listener3);
out_layout.addView(layout, param);
LinearLayout.LayoutParams param2 =
new LinearLayout.LayoutParams(WC, WC);
param2.topMargin = 30;
out_layout.addView(btn3, param2);
setContentView(out_layout);
}
OnClickListener listener = new OnClickListener(){
public void onClick(View v) { setTitle("this is OK button"); }
};
OnClickListener listener2 = new OnClickListener() {
public void onClick(View v) { finish(); }
};
OnClickListener listener3 = new OnClickListener() {
public void onClick(View v){ setTitle("this is Cancel button"); }
};
}