Java tutorial
package org.smssecure.smssecure.preferences; /* * Copyright 2013 Google Inc. * * 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. */ import android.app.Activity; import android.app.AlertDialog; import android.app.Dialog; import android.content.Context; import android.content.res.Resources; import android.content.res.TypedArray; import android.graphics.drawable.BitmapDrawable; import android.graphics.drawable.Drawable; import android.graphics.drawable.GradientDrawable; import android.graphics.drawable.LayerDrawable; import android.os.Bundle; import android.preference.Preference; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.GridLayout; import android.util.AttributeSet; import android.util.DisplayMetrics; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.widget.ImageView; import android.widget.TextView; import org.smssecure.smssecure.R; /** * A preference that allows the user to choose an application or shortcut. */ public class ColorPreference extends Preference { private int[] mColorChoices = {}; private int mValue = 0; private int mItemLayoutId = R.layout.color_preference_item; private int mNumColumns = 5; private View mPreviewView; public ColorPreference(Context context) { super(context); initAttrs(null, 0); } public ColorPreference(Context context, AttributeSet attrs) { super(context, attrs); initAttrs(attrs, 0); } public ColorPreference(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); initAttrs(attrs, defStyle); } private void initAttrs(AttributeSet attrs, int defStyle) { TypedArray a = getContext().getTheme().obtainStyledAttributes(attrs, R.styleable.ColorPreference, defStyle, defStyle); try { mItemLayoutId = a.getResourceId(R.styleable.ColorPreference_itemLayout, mItemLayoutId); mNumColumns = a.getInteger(R.styleable.ColorPreference_numColumns, mNumColumns); // int choicesResId = a.getResourceId(R.styleable.ColorPreference_choices, // R.array.default_color_choice_values); // if (choicesResId > 0) { // String[] choices = a.getResources().getStringArray(choicesResId); // mColorChoices = new int[choices.length]; // for (int i = 0; i < choices.length; i++) { // mColorChoices[i] = Color.parseColor(choices[i]); // } // } } finally { a.recycle(); } setWidgetLayoutResource(mItemLayoutId); } @Override protected void onBindView(View view) { super.onBindView(view); mPreviewView = view.findViewById(R.id.color_view); setColorViewValue(mPreviewView, mValue, false); } public void setValue(int value) { if (callChangeListener(value)) { mValue = value; persistInt(value); notifyChanged(); } } public void setChoices(int[] values) { mColorChoices = values; } @Override protected void onClick() { super.onClick(); ColorDialogFragment fragment = ColorDialogFragment.newInstance(); fragment.setPreference(this); ((AppCompatActivity) getContext()).getSupportFragmentManager().beginTransaction() .add(fragment, getFragmentTag()).commit(); } @Override protected void onAttachedToActivity() { super.onAttachedToActivity(); AppCompatActivity activity = (AppCompatActivity) getContext(); ColorDialogFragment fragment = (ColorDialogFragment) activity.getSupportFragmentManager() .findFragmentByTag(getFragmentTag()); if (fragment != null) { // re-bind preference to fragment fragment.setPreference(this); } } @Override protected Object onGetDefaultValue(TypedArray a, int index) { return a.getInt(index, 0); } @Override protected void onSetInitialValue(boolean restoreValue, Object defaultValue) { setValue(restoreValue ? getPersistedInt(0) : (Integer) defaultValue); } public String getFragmentTag() { return "color_" + getKey(); } public int getValue() { return mValue; } public static class ColorDialogFragment extends android.support.v4.app.DialogFragment { private ColorPreference mPreference; private GridLayout mColorGrid; public ColorDialogFragment() { } public static ColorDialogFragment newInstance() { return new ColorDialogFragment(); } public void setPreference(ColorPreference preference) { mPreference = preference; repopulateItems(); } @Override public void onAttach(Activity activity) { super.onAttach(activity); repopulateItems(); } @Override public Dialog onCreateDialog(Bundle savedInstanceState) { LayoutInflater layoutInflater = LayoutInflater.from(getActivity()); View rootView = layoutInflater.inflate(R.layout.color_preference_items, null); mColorGrid = (GridLayout) rootView.findViewById(R.id.color_grid); mColorGrid.setColumnCount(mPreference.mNumColumns); repopulateItems(); return new AlertDialog.Builder(getActivity()).setView(rootView).create(); } private void repopulateItems() { if (mPreference == null || mColorGrid == null) { return; } Context context = mColorGrid.getContext(); mColorGrid.removeAllViews(); for (final int color : mPreference.mColorChoices) { View itemView = LayoutInflater.from(context).inflate(R.layout.color_preference_item, mColorGrid, false); setColorViewValue(itemView.findViewById(R.id.color_view), color, color == mPreference.getValue()); itemView.setClickable(true); itemView.setFocusable(true); itemView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { mPreference.setValue(color); dismiss(); } }); mColorGrid.addView(itemView); } sizeDialog(); } @Override public void onStart() { super.onStart(); sizeDialog(); } private void sizeDialog() { // if (mPreference == null || mColorGrid == null) { // return; // } // // Dialog dialog = getDialog(); // if (dialog == null) { // return; // } // // final Resources res = mColorGrid.getContext().getResources(); // DisplayMetrics dm = res.getDisplayMetrics(); // // // Can't use Integer.MAX_VALUE here (weird issue observed otherwise on 4.2) // mColorGrid.measure( // View.MeasureSpec.makeMeasureSpec(dm.widthPixels, View.MeasureSpec.AT_MOST), // View.MeasureSpec.makeMeasureSpec(dm.heightPixels, View.MeasureSpec.AT_MOST)); // int width = mColorGrid.getMeasuredWidth(); // int height = mColorGrid.getMeasuredHeight(); // // int extraPadding = res.getDimensionPixelSize(R.dimen.color_grid_extra_padding); // // width += extraPadding; // height += extraPadding; // // dialog.getWindow().setLayout(width, height); } } private static void setColorViewValue(View view, int color, boolean selected) { if (view instanceof ImageView) { ImageView imageView = (ImageView) view; Resources res = imageView.getContext().getResources(); Drawable currentDrawable = imageView.getDrawable(); GradientDrawable colorChoiceDrawable; if (currentDrawable instanceof GradientDrawable) { // Reuse drawable colorChoiceDrawable = (GradientDrawable) currentDrawable; } else { colorChoiceDrawable = new GradientDrawable(); colorChoiceDrawable.setShape(GradientDrawable.OVAL); } // Set stroke to dark version of color // int darkenedColor = Color.rgb( // Color.red(color) * 192 / 256, // Color.green(color) * 192 / 256, // Color.blue(color) * 192 / 256); colorChoiceDrawable.setColor(color); // colorChoiceDrawable.setStroke((int) TypedValue.applyDimension( // TypedValue.COMPLEX_UNIT_DIP, 2, res.getDisplayMetrics()), darkenedColor); Drawable drawable = colorChoiceDrawable; if (selected) { BitmapDrawable checkmark = (BitmapDrawable) res.getDrawable(R.drawable.check); checkmark.setGravity(Gravity.CENTER); drawable = new LayerDrawable(new Drawable[] { colorChoiceDrawable, checkmark }); } imageView.setImageDrawable(drawable); } else if (view instanceof TextView) { ((TextView) view).setTextColor(color); } } }