Yaaic/application/src/org/yaaic/view/ConversationLayout.java

/*
Yaaic - Yet Another Android IRC Client

Copyright 2009-2011 Sebastian Kaspari

This file is part of Yaaic.

Yaaic is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Yaaic is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Yaaic.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.yaaic.view;

import org.yaaic.model.Settings;

import android.app.Activity;
import android.content.Context;
import android.content.res.Configuration;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.LinearLayout;

/**
 * ConversationLayout: LinearLayout that resizes correctly when an IME
 * comes up in fullscreen mode
 * 
 * @author Steven Luo <steven+android@steven676.net>
 */
public class ConversationLayout extends LinearLayout
{
    Activity activity;
    int curHeight = 0;
    boolean fullscreen = false, isLandscape = false;
    boolean redoLayout = false;

    /**
     * Create a new conversation view switcher
     * 
     * @param context
     */
    public ConversationLayout(Context context)
    {
        super(context);
        doInit(context);
    }

    /**
     * Create a new conversation view switcher
     * 
     * @param context
     * @param attrs
     */
    public ConversationLayout(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        doInit(context);
    }

    /**
     * Initialize the ConversationLayout
     */
    private void doInit(Context context)
    {
        activity = (Activity) context;
        fullscreen = (new Settings(context)).fullscreenConversations();
        isLandscape = (activity.getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE);
    }

    /**
     * Get the height of the window's visible area
     */
    private int getWindowHeight()
    {
        Rect visible = new Rect();
        getWindowVisibleDisplayFrame(visible);
        return visible.height();
    }

    /**
     * onMeasure (ask the view how much space it wants)
     * This is called when the window size changes, so we can hook into it to
     * resize ourselves when the IME comes up
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
    {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        /* XXX: We should probably use some heuristic of how many pixels are
           available for deciding whether to scroll instead of resize, instead
           of refusing to resize in landscape */
        if (!fullscreen || isLandscape) {
            return;
        }

        int height = getWindowHeight();
        if (curHeight != height) {
            curHeight = height;
            FrameLayout.LayoutParams params = new FrameLayout.LayoutParams(
                FrameLayout.LayoutParams.FILL_PARENT,
                height
            );
            params.gravity = Gravity.BOTTOM | Gravity.CLIP_VERTICAL;
            setLayoutParams(params);
            redoLayout = true;
        }
    }

    /**
     * onDraw (draw the view)
     */
    @Override
    protected void onDraw(Canvas canvas)
    {
        if (redoLayout) {
            // Layout params have changed -- force a layout update
            requestLayout();
            redoLayout = false;
        }
        super.onDraw(canvas);
    }
}