setLayoutParams doesn't work second time

问题

I have written the following code to first increase the size of ImageView and after 100ms decrease the size of the same ImageView. However this code increases the size of ImageView but it doesn't decrease it's size or the code after 100ms delay doesn't affect the imageView dimensions.

What am I doing wrong?

uiHandler.post(new Runnable()
{
    @Override
    public void run()
    {
        FrameLayout.LayoutParams layout = (android.widget.FrameLayout.LayoutParams) imageView.getLayoutParams();
        layout.height = (int) (2*iconsSizeInDP);
        layout.width = (int) (2*iconsSizeInDP);
        imageView.setLayoutParams(layout);
        try
        {
            Thread.sleep(50);
        }
        catch (InterruptedException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        Toast.makeText(getApplicationContext(), "Hello", Toast.LENGTH_SHORT).show();
        // following code block doesnt'affect imageView dimensions
        layout.height = (int) iconsSizeInDP;
        layout.width = (int) iconsSizeInDP;
        imageView.setLayoutParams(layout);
    }
});

Regards

回答1:

You change the layout 2 times in the same UI thread, so only the last change can take effect. You should separate to 2 UI thread, like this:

uiHandler.post(new Runnable()
{
    @Override
    public void run()
    {
        FrameLayout.LayoutParams layout = (android.widget.FrameLayout.LayoutParams) imageView.getLayoutParams();
        layout.height = (int) (2*iconsSizeInDP);
        layout.width = (int) (2*iconsSizeInDP);
        imageView.setLayoutParams(layout);
    }
};
uiHandler.postDelayed(new Runnable()
{
    @Override
    public void run()
    {
        Toast.makeText(getApplicationContext(), "Hello", Toast.LENGTH_SHORT).show();
        // following code block doesnt'affect imageView dimensions
        layout.height = (int) iconsSizeInDP;
        layout.width = (int) iconsSizeInDP;
        imageView.setLayoutParams(layout);
    }
},50);

回答2:

please have a look on the line FrameLayout.LayoutParams layout = (android.widget.FrameLayout.LayoutParams) imageView.getLayoutParams();

please have a look when have a try to make FrameLayout.LayoutParams layout global

来源：https://stackoverflow.com/questions/21086859/setlayoutparams-doesnt-work-second-time

标签

java

android

view

layoutparams