None of those are precisely the same, though they will all have the same net effect. The difference between the first and the second is that if you happen to be on the main application thread when executing the code, the first one (runOnUiThread()) will execute the Runnable immediately. The second one (post()) always puts … Read more
As stated in Constraint Layout guides: If a view has no constraints when you run your layout on a device, it is drawn at position [0,0] (the top-left corner). You must add at least one horizontal and one vertical constraint for the view. I guess you haven’t applied any constraints. Either manually apply constraints to … Read more
Let’s say you generate a bunch of views that are similar. You could set an OnClickListener for each view individually: button1.setOnClickListener(new OnClickListener … ); button2.setOnClickListener(new OnClickListener … ); … Then you have to create a unique onClick method for each view even if they do the similar things, like: public void onClick(View v) { doAction(1); … Read more
There isn’t an easy way like listview.addHeaderView() but you can achieve this by adding a type to your adapter for header. Here is an example public class HeaderAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { private static final int TYPE_HEADER = 0; private static final int TYPE_ITEM = 1; String[] data; public HeaderAdapter(String[] data) { this.data = data; } … Read more
From API level 17 and above, you can call: View.generateViewId() Then use View.setId(int). If your app is targeted lower than API level 17, use ViewCompat.generateViewId()
findViewByID returns null
you can create button from code. you can find all the alternative methods of setting attribute in the doc. for example Button button = new Button(this); button.setText(“hi”); button.setId(Id); button.setTextColor(Color.Red); button.setBackgroundResource(R.drawable.icon); buttonlayout.addView(button);
There is no “make a sawtooth border” option as far as I know, so you can do one of these things: Find/make the background image with the pattern you want and add it as a drawable background (or just apply it on the edges you want) Generate this pattern in the app using lines of … Read more