Android example source code file (ListViewHeight.java)

This example Android source code file (ListViewHeight.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

abbaye, abertam, abondance, activity, android, app, application, arrayadapter, belloc, cats, framelayout, linearlayout, listviewheight, mont, os, override, string, ui, view, widget

The ListViewHeight.java Android example source code

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.widget.listview;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import com.android.frameworks.coretests.R;

public class ListViewHeight extends Activity {

    private View mButton1;
    private View mButton2;
    private View mButton3;
    
    private View mOuterLayout;
    private ListView mInnerList;

    ArrayAdapter<String> mAdapter;
    private String[] mStrings = {
            "Abbaye de Belloc", "Abbaye du Mont des Cats", "Abertam", "Abondance", "Ackawi" };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.linear_layout_listview_height);

        mButton1 = findViewById(R.id.button1);
        mButton2 = findViewById(R.id.button2);
        mButton3 = findViewById(R.id.button3);
        
        mOuterLayout = findViewById(R.id.layout);
        mInnerList = (ListView)findViewById(R.id.inner_list);
        
        mAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_dropdown_item_1line, 
                                            mStrings);

        // Clicking this button will show the list view and set it to a fixed height
        // If you then hide the views, there is no problem.
        mButton1.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                // set listview to fixed height 
                ViewGroup.MarginLayoutParams lp;
                lp = (ViewGroup.MarginLayoutParams) mInnerList.getLayoutParams();
                lp.height = 200;
                mInnerList.setLayoutParams(lp);
                // enable list adapter
                mInnerList.setAdapter(mAdapter);
                // and show it
                mOuterLayout.setVisibility(View.VISIBLE);
            }
        });

        // Clicking this button will show the list view and set it match_parent height
        // If you then hide the views, there is an NPE when calculating the ListView height.
        mButton2.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                // set listview to fill screen
                ViewGroup.MarginLayoutParams lp;
                lp = (ViewGroup.MarginLayoutParams) mInnerList.getLayoutParams();
                lp.height = lp.MATCH_PARENT;
                mInnerList.setLayoutParams(lp);
                // enable list adapter
                mInnerList.setAdapter(mAdapter);
                // and show it
                mOuterLayout.setVisibility(View.VISIBLE);
            }
        });

        // Clicking this button will remove the list adapter and hide the outer enclosing view.
        // We have to climb all the way to the top because the bug (not checking visibility)
        // only occurs at the very outer loop of ViewRoot.performTraversals and in the case of
        // an Activity, this means you have to crawl all the way out to the root view.
        // In the search manager, it's sufficient to simply show/hide the outer search manager
        // view to trigger the same bug.
        mButton3.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                mInnerList.setAdapter(null);
                // hide listview's owner
                // as it turns out, the owner doesn't take us high enough
                // because our activity includes a title bar, thus another layer
                View parent = (View) mOuterLayout.getParent();      // FrameLayout (app container)
                View grandpa = (View) parent.getParent();           // LinearLayout (title+app)
                View great = (View) grandpa.getParent();            // PhoneWindow.DecorView
                great.setVisibility(View.GONE);
            }
        });
    }

}