I am trying to building a linear layout programmatically, in which, there are 4 buttons in all, each of the button simply positioned below the previous button. Just like the picture shows below:
And as you can see from the picture above, each button has exactly the same size but they have different layout_margins, the first button has a larger value in layout_marginTop while the other 3 buttons has the same value in layout_marginTop.
Basically to build a layout like this by xml is very simple but now I have really come across difficulties in building all this only through java code. I have gone through many posts and now I can easily add 4 buttons in proper sizes but I just could not find a proper way to programmatically set the layout_margin for each of the button.
To simple add four buttons, I could do like this:
public class mainActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LinearLayout layout = new LinearLayout(this);
layout.setOrientation(LinearLayout.VERTICAL); //Can also be done in xml by android:orientation="vertical"
for (int i = 0; i < 3; i++) {
LinearLayout row = new LinearLayout(this);
row.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
for (int j = 0; j < 4; j++) {
Button btnTag = new Button(this);
btnTag.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
btnTag.setText("Button " + (j + 1 + (i * 4 )));
btnTag.setId(j + 1 + (i * 4));
row.addView(btnTag);
}
layout.addView(row);
}
setContentView(layout);
//setContentView(R.layout.main);
}
}
And to programmatically set margins for each button(view), I could do like this:
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.setMargins(0, 2, 0, 0);
button.setLayoutParams(params);
But here comes the problem: as long as I setLayoutParams for the 4 buttons, and then add 4 buttons into Linearlayout by "addView(button)", only the first button could be displayed in the proper size with the proper margins. All the other 3 buttons just disappeared. And With many tests I just found it seems that only one layoutParams could be allowed in a linearlayout object. As a result, as long as I set different layout params for different buttons, only the first button could be displayed. But since here the margin params for my 4 buttons are definitely different thus I think I have to use different layoutparams for different buttons.
So pls anyone tell me how could I programmatically set the margin for my each of my buttons and make them display properlly? This has already sucked my life for two days, pls help! :)