frameworks_base/packages/Keyguard/src/com/android/keyguard/KeyguardMessageArea.java

/*
 * Copyright (C) 2011 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 com.android.keyguard;

import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.ObjectAnimator;
import android.content.Context;
import android.os.Handler;
import android.os.Looper;
import android.os.SystemClock;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.util.MutableInt;
import android.view.View;
import android.widget.TextView;

import java.lang.ref.WeakReference;

import com.android.internal.widget.LockPatternUtils;

/***
 * Manages a number of views inside of the given layout. See below for a list of widgets.
 */
class KeyguardMessageArea extends TextView {
    /** Handler token posted with accessibility announcement runnables. */
    private static final Object ANNOUNCE_TOKEN = new Object();

    /**
     * Delay before speaking an accessibility announcement. Used to prevent
     * lift-to-type from interrupting itself.
     */
    private static final long ANNOUNCEMENT_DELAY = 250;

    static final int SECURITY_MESSAGE_DURATION = 5000;
    protected static final int FADE_DURATION = 750;

    private static final String TAG = "KeyguardMessageArea";

    // is the bouncer up?
    boolean mShowingBouncer = false;

    KeyguardUpdateMonitor mUpdateMonitor;

    // Timeout before we reset the message to show charging/owner info
    long mTimeout = SECURITY_MESSAGE_DURATION;

    private Handler mHandler;

    CharSequence mMessage;
    boolean mShowingMessage;
    private CharSequence mSeparator;
    private LockPatternUtils mLockPatternUtils;

    Runnable mClearMessageRunnable = new Runnable() {
        @Override
        public void run() {
            mMessage = null;
            mShowingMessage = false;
            if (mShowingBouncer) {
                hideMessage(FADE_DURATION, true);
            } else {
                update();
            }
        }
    };

    public static class Helper implements SecurityMessageDisplay {
        KeyguardMessageArea mMessageArea;
        Helper(View v) {
            mMessageArea = (KeyguardMessageArea) v.findViewById(R.id.keyguard_message_area);
            if (mMessageArea == null) {
                throw new RuntimeException("Can't find keyguard_message_area in " + v.getClass());
            }
        }

        @Override
        public void setMessage(CharSequence msg, boolean important) {
            if (!TextUtils.isEmpty(msg) && important) {
                mMessageArea.mMessage = msg;
                mMessageArea.securityMessageChanged();
            } else {
                mMessageArea.clearMessage();
            }
        }

        @Override
        public void setMessage(int resId, boolean important) {
            if (resId != 0 && important) {
                mMessageArea.mMessage = mMessageArea.getContext().getResources().getText(resId);
                mMessageArea.securityMessageChanged();
            } else {
                mMessageArea.clearMessage();
            }
        }

        @Override
        public void setMessage(int resId, boolean important, Object... formatArgs) {
            if (resId != 0 && important) {
                mMessageArea.mMessage = mMessageArea.getContext().getString(resId, formatArgs);
                mMessageArea.securityMessageChanged();
            } else {
                mMessageArea.clearMessage();
            }
        }

        @Override
        public void showBouncer(int duration) {
            mMessageArea.hideMessage(duration, false);
            mMessageArea.mShowingBouncer = true;
        }

        @Override
        public void hideBouncer(int duration) {
            mMessageArea.showMessage(duration);
            mMessageArea.mShowingBouncer = false;
        }

        @Override
        public void setTimeout(int timeoutMs) {
            mMessageArea.mTimeout = timeoutMs;
        }
    }

    private KeyguardUpdateMonitorCallback mInfoCallback = new KeyguardUpdateMonitorCallback() {
        public void onScreenTurnedOff(int why) {
            setSelected(false);
        };
        public void onScreenTurnedOn() {
            setSelected(true);
        };
    };

    public KeyguardMessageArea(Context context) {
        this(context, null);
    }

    public KeyguardMessageArea(Context context, AttributeSet attrs) {
        super(context, attrs);
        setLayerType(LAYER_TYPE_HARDWARE, null); // work around nested unclipped SaveLayer bug

        mLockPatternUtils = new LockPatternUtils(context);

        // Registering this callback immediately updates the battery state, among other things.
        mUpdateMonitor = KeyguardUpdateMonitor.getInstance(getContext());
        mUpdateMonitor.registerCallback(mInfoCallback);
        mHandler = new Handler(Looper.myLooper());

        mSeparator = getResources().getString(
                com.android.internal.R.string.kg_text_message_separator);

        update();
    }

    @Override
    protected void onFinishInflate() {
        final boolean screenOn = KeyguardUpdateMonitor.getInstance(mContext).isScreenOn();
        setSelected(screenOn); // This is required to ensure marquee works
    }

    public void securityMessageChanged() {
        setAlpha(1f);
        mShowingMessage = true;
        update();
        mHandler.removeCallbacks(mClearMessageRunnable);
        if (mTimeout > 0) {
            mHandler.postDelayed(mClearMessageRunnable, mTimeout);
        }
        mHandler.removeCallbacksAndMessages(ANNOUNCE_TOKEN);
        mHandler.postAtTime(new AnnounceRunnable(this, getText()), ANNOUNCE_TOKEN,
                (SystemClock.uptimeMillis() + ANNOUNCEMENT_DELAY));
    }

    public void clearMessage() {
        mHandler.removeCallbacks(mClearMessageRunnable);
        mHandler.post(mClearMessageRunnable);
    }

    /**
     * Update the status lines based on these rules:
     * AlarmStatus: Alarm state always gets it's own line.
     * Status1 is shared between help, battery status and generic unlock instructions,
     * prioritized in that order.
     * @param showStatusLines status lines are shown if true
     */
    void update() {
        MutableInt icon = new MutableInt(0);
        CharSequence status = getCurrentMessage();
        setCompoundDrawablesWithIntrinsicBounds(icon.value, 0, 0, 0);
        setText(status);
    }


    CharSequence getCurrentMessage() {
        return mShowingMessage ? mMessage : null;
    }

    private void hideMessage(int duration, boolean thenUpdate) {
        if (duration > 0) {
            Animator anim = ObjectAnimator.ofFloat(this, "alpha", 0f);
            anim.setDuration(duration);
            if (thenUpdate) {
                anim.addListener(new AnimatorListenerAdapter() {
                        @Override
                            public void onAnimationEnd(Animator animation) {
                            update();
                        }
                });
            }
            anim.start();
        } else {
            setAlpha(0f);
            if (thenUpdate) {
                update();
            }
        }
    }

    private void showMessage(int duration) {
        if (duration > 0) {
            Animator anim = ObjectAnimator.ofFloat(this, "alpha", 1f);
            anim.setDuration(duration);
            anim.start();
        } else {
            setAlpha(1f);
        }
    }

    /**
     * Runnable used to delay accessibility announcements.
     */
    private static class AnnounceRunnable implements Runnable {
        private final WeakReference<View> mHost;
        private final CharSequence mTextToAnnounce;

        public AnnounceRunnable(View host, CharSequence textToAnnounce) {
            mHost = new WeakReference<View>(host);
            mTextToAnnounce = textToAnnounce;
        }

        @Override
        public void run() {
            final View host = mHost.get();
            if (host != null) {
                host.announceForAccessibility(mTextToAnnounce);
            }
        }
    }
}