如何动态添加视图到LinearLayout？

Question

Is there a way to dynamically add and position images into a linear layout in android? in php I could just echo out an image tag and use css to position it, not really sure how to tackle this in android however as the xml seems to be very rigidly predefined.

Answer 1

You can add view to any ViewGroup by calling the ViewGroup.addView(View) method. How ever, this is kind of a vague way of adding a View. What is preferred is that you first create a LayoutParams for the given layout (with the view in mind) This will allow you to control the view and its relationship with its parent view more intimately.

Here is a sample to tie everything together:

class MyActivity extends Activity {
    @Override public void onCreate(Bundle icicle) {
        super.onCreate(icicle)

        LinearLayout ll = new LinearLayout(this);
        ll.setOrientation(LinearLayout.VERTICAL);
        // Create 5 view to take up a small amount of space.

        View tmp = null;

        for (int i = 0; i < 5; i++) {
            tmp = new View(this);
            ll.addView(tmpnew LinearLayout.LayoutParams(
                50, // Width
                50);    // Height
            // Either or both the width and height may be ViewGroup.
            // (WRAP_CONTENT || FILL_PARENT || MATCH_PARENT)
        }

        setContentView(ll);
    }
}

This is how you would dynamically add a view to a LinearLayout. However, due to the structure and design of a LinearLayout, there really isn't much in the way of positioning. Think of a LinearLayout as an array full of views in one direction, the only thing you can do is change where they are in the array. If you want fine control over a View, I recommend a RelativeLayout.