Android example source code file (ListItemFactory.java)

This example Android source code file (ListItemFactory.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

android, button, content, context, illegalargumentexception, left, linearlayout, listitemfactory, middle, right, slot, string, textview, ui, view, widget

The ListItemFactory.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.util;

import android.content.Context;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

/**
 * Reusable methods for creating more complex list items.
 */
public class ListItemFactory {

    /**
     * Create a view with a button at the top and bottom, with filler in between.
     * The filler is sized to take up any space left over within desiredHeight.
     *
     * @param position      The position within the list.
     * @param context       The context.
     * @param desiredHeight The desired height of the entire view.
     * @return The created view.
     */
    public static View twoButtonsSeparatedByFiller(int position, Context context, int desiredHeight) {
        if (desiredHeight < 90) {
            throw new IllegalArgumentException("need at least 90 pixels of height " +
                    "to create the two buttons and leave 10 pixels for the filler");
        }

        final LinearLayout ll = new LinearLayout(context);
        ll.setOrientation(LinearLayout.VERTICAL);

        final LinearLayout.LayoutParams buttonLp =
                new LinearLayout.LayoutParams(
                        ViewGroup.LayoutParams.MATCH_PARENT,
                        50);

        final Button topButton = new Button(context);
        topButton.setLayoutParams(
                buttonLp);
        topButton.setText("top (position " + position + ")");
        ll.addView(topButton);

        final TextView middleFiller = new TextView(context);
        middleFiller.setLayoutParams(new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                desiredHeight - 100));
        middleFiller.setText("filler");
        ll.addView(middleFiller);

        final Button bottomButton = new Button(context);
        bottomButton.setLayoutParams(buttonLp);
        bottomButton.setText("bottom (position " + position + ")");
        ll.addView(bottomButton);
        ll.setTag("twoButtons");
        return ll;
    }

    public enum Slot {
        Left,
        Middle,
        Right
    }

    /**
     * Create a horizontal linear layout divided into thirds (with some margins
     * separating the thirds), filled with buttons into some slots.
     * @param context The context.
     * @param desiredHeight The height of the LL.
     * @param slots Which slots to fill with buttons.
     * @return The linear layout.
     */
    public static View horizontalButtonSlots(Context context, int desiredHeight, Slot... slots) {

        final LinearLayout ll = new LinearLayout(context);
        ll.setOrientation(LinearLayout.HORIZONTAL);

        final LinearLayout.LayoutParams lp
                = new LinearLayout.LayoutParams(0, desiredHeight);
        lp.setMargins(10, 0, 10, 0);
        lp.weight = 0.33f;

        boolean left = false;
        boolean middle = false;
        boolean right = false;
        for (Slot slot : slots) {
            switch (slot) {
                case Left:
                    left = true;
                    break;
                case Middle:
                    middle = true;
                    break;
                case Right:
                    right = true;
                    break;
            }
        }

        if (left) {
            final Button button = new Button(context);
            button.setText("left");
            ll.addView(button, lp);
        } else {
           ll.addView(new View(context), lp);
        }

        if (middle) {
            final Button button = new Button(context);
            button.setText("center");
            ll.addView(button, lp);
        } else {
           ll.addView(new View(context), lp);
        }

        if (right) {
            final Button button = new Button(context);
            button.setText("right");
            ll.addView(button, lp);
        } else {
           ll.addView(new View(context), lp);
        }

        return ll;
    }


    /**
     * Create a button ready to be a list item.
     *
     * @param position      The position within the list.
     * @param context       The context.
     * @param text          The text of the button
     * @param desiredHeight The desired height of the button
     * @return The created view.
     */
    public static View button(int position, Context context, String text, int desiredHeight) {
        TextView result = new Button(context);
        result.setHeight(desiredHeight);
        result.setText(text);
        final ViewGroup.LayoutParams lp = new AbsListView.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.WRAP_CONTENT);
        result.setLayoutParams(lp);
        result.setId(position);
        result.setTag("button");
        return result;
    }
    
    /**
     * Convert an existing button view to display the data at a new position.
     * 
     * @param convertView Non-null Button created by {@link #button}
     * @param text The text of the button
     * @param position The position withion the list
     * @return The converted view
     */
    public static View convertButton(View convertView, String text, int position) {
        if (((String) convertView.getTag()).equals("button")) {
            ((Button) convertView).setText(text);
            convertView.setId(position);
            return convertView;
        } else {
            return null;
        }
    }
    
    /**
     * Create a text view ready to be a list item.
     *
     * @param position      The position within the list.
     * @param context       The context.
     * @param text          The text to display
     * @param desiredHeight The desired height of the text view
     * @return The created view.
     */
    public static View text(int position, Context context, String text, int desiredHeight) {
        TextView result = new TextView(context);
        result.setHeight(desiredHeight);
        result.setText(text);
        final ViewGroup.LayoutParams lp = new AbsListView.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.WRAP_CONTENT);
        result.setLayoutParams(lp);
        result.setId(position);
        result.setTag("text");
        return result;
    }
    
    /**
     * Convert an existing text view to display the data at a new position.
     * 
     * @param convertView Non-null TextView created by {@link #text}
     * @param text The text to display
     * @param position The position withion the list
     * @return The converted view
     */
    public static View convertText(View convertView, String text, int position) {
        if(convertView.getTag() != null && ((String) convertView.getTag()).equals("text")) {
            ((TextView) convertView).setText(text);
            convertView.setId(position);
            return convertView;

        } else {
            return null;
        }
    }
    
    /**
     * Create a text view ready to be a list item.
     *
     * @param position      The position within the list.
     * @param context       The context.
     * @param text          The text of the button
     * @param desiredHeight The desired height of the button
     * @return The created view.
     */
    public static View doubleText(int position, Context context, String text, int desiredHeight) {
        final LinearLayout ll = new LinearLayout(context);
        ll.setOrientation(LinearLayout.HORIZONTAL);

        final AbsListView.LayoutParams lp =
                new AbsListView.LayoutParams(
                        ViewGroup.LayoutParams.MATCH_PARENT,
                        desiredHeight);
        ll.setLayoutParams(lp);
        ll.setId(position);
        
        TextView t1 = new TextView(context);
        t1.setHeight(desiredHeight);
        t1.setText(text);
        t1.setGravity(Gravity.LEFT | Gravity.CENTER_VERTICAL);
        final ViewGroup.LayoutParams lp1 = new LinearLayout.LayoutParams(
                0,
                ViewGroup.LayoutParams.WRAP_CONTENT, 1.0f);
        ll.addView(t1, lp1);
        
        TextView t2 = new TextView(context);
        t2.setHeight(desiredHeight);
        t2.setText(text);
        t2.setGravity(Gravity.RIGHT | Gravity.CENTER_VERTICAL);
        final ViewGroup.LayoutParams lp2 = new LinearLayout.LayoutParams(
                0,
                ViewGroup.LayoutParams.WRAP_CONTENT,
                1.0f);

        ll.addView(t2, lp2);
        ll.setTag("double");
        return ll;
    }

    
    /**
     * Convert an existing button view to display the data at a new position.
     * 
     * @param convertView Non-null view created by {@link #doubleText}
     * @param text The text of the button
     * @param position The position withion the list
     * @return The converted view
     */
    public static View convertDoubleText(View convertView, String text, int position) {
        if (((String) convertView.getTag()).equals("double")) {
            TextView t1 = (TextView) ((LinearLayout) convertView).getChildAt(0);
            TextView t2 = (TextView) ((LinearLayout) convertView).getChildAt(1);
            t1.setText(text);
            t2.setText(text);
            convertView.setId(position);
            return convertView;
        } else {
            return null;
        }
    }
}