packages/SystemUI/src/com/android/systemui/statusbar/tablet/InputMethodButton.java

/*
 * Copyright (C) 2010 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.systemui.statusbar.tablet;

import android.content.Context;
import android.os.IBinder;
import android.provider.Settings;
import android.util.AttributeSet;
import android.view.inputmethod.InputMethodInfo;
import android.view.inputmethod.InputMethodManager;
import android.view.View;
import android.widget.ImageView;

import com.android.systemui.R;

import java.util.List;

public class InputMethodButton extends ImageView {

    private static final String  TAG = "StatusBar/InputMethodButton";
    private static final boolean DEBUG = false;

    // These values are defined in Settings application.
    private static final int ID_IME_BUTTON_VISIBILITY_AUTO = 0;
    private static final int ID_IME_BUTTON_VISIBILITY_ALWAYS_SHOW = 1;
    private static final int ID_IME_BUTTON_VISIBILITY_ALWAYS_HIDE = 2;

    // other services we wish to talk to
    private final InputMethodManager mImm;
    private final int mId;
    private ImageView mIcon;
    private IBinder mToken;
    private boolean mShowButton = false;
    private boolean mScreenLocked = false;
    private boolean mHardKeyboardAvailable;

    public InputMethodButton(Context context, AttributeSet attrs) {
        super(context, attrs);

        // Resource Id of the input method button. This id is defined in status_bar.xml
        mId = getId();
        // IME hookup
        mImm = (InputMethodManager) context.getSystemService(Context.INPUT_METHOD_SERVICE);
    }

    @Override
    protected void onAttachedToWindow() {
        mIcon = (ImageView) findViewById(mId);

        refreshStatusIcon();
    }

    // Display IME switcher icon only when all of the followings are true:
    // * There is only one enabled IME on the device.  (Note that the IME should be the system IME)
    // * There are no explicitly enabled (by the user) subtypes of the IME, or the IME doesn't have
    // its subtypes at all
    private boolean needsToShowIMEButton() {
        if (!mShowButton || mScreenLocked) return false;

        if (mHardKeyboardAvailable) {
            return true;
        }

        List<InputMethodInfo> imis = mImm.getEnabledInputMethodList();
        final int size = imis.size();
        final int visibility = loadInputMethodSelectorVisibility();
        switch (visibility) {
            case ID_IME_BUTTON_VISIBILITY_AUTO:
                return size > 1 || (size == 1
                        && mImm.getEnabledInputMethodSubtypeList(imis.get(0), false).size() > 1);
            case ID_IME_BUTTON_VISIBILITY_ALWAYS_SHOW:
                return true;
            case ID_IME_BUTTON_VISIBILITY_ALWAYS_HIDE:
                return false;
        }
        return false;
    }

    private void refreshStatusIcon() {
        if (mIcon == null) {
            return;
        }
        if (!needsToShowIMEButton()) {
            setVisibility(View.GONE);
            return;
        } else {
            setVisibility(View.VISIBLE);
        }
        mIcon.setImageResource(R.drawable.ic_sysbar_ime);
    }

    private int loadInputMethodSelectorVisibility() {
        return Settings.Secure.getInt(getContext().getContentResolver(),
                Settings.Secure.INPUT_METHOD_SELECTOR_VISIBILITY, ID_IME_BUTTON_VISIBILITY_AUTO);
    }

    public void setIconImage(int resId) {
        if (mIcon != null) {
            mIcon.setImageResource(resId);
        }
    }

    public void setImeWindowStatus(IBinder token, boolean showButton) {
        mToken = token;
        mShowButton = showButton;
        refreshStatusIcon();
    }

    public void setHardKeyboardStatus(boolean available) {
        if (mHardKeyboardAvailable != available) {
            mHardKeyboardAvailable = available;
            refreshStatusIcon();
        }
    }

    public void setScreenLocked(boolean locked) {
        mScreenLocked = locked;
        refreshStatusIcon();
    }
}