最近一段時間都沒有更新文章，趁工作之余，更新一篇。
今天介紹一個很常見效果也最容易被忽略的彈出框：ActionMode。主要是ActionMode使用和自己使用過程中遇到的一些問題，相對還是比較簡單的。
1、ActionMode的基本使用
2、使用ActionMode遇到的一些問題
ActionMode
1、ActionMode的基本使用
主要分兩步：
1、實現ActionMode.Callback接口
2、調用startActionMode或者startSupportActionMode
1、實現ActionMode.Callback接口
ActionMode.Callback
對于ActionMode.Callback，我們需要實現其四個方法：
new ActionMode.Callback() {
//Called when action mode is first created.
// The menu supplied will be used to generate action buttons for the action mode
//當ActionMode第一次被創建的時候調用
//可在這里初始化menu
@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
MenuInflater inflater = mode.getMenuInflater();
inflater.inflate(R.menu.menu, menu);
menu.findItem(R.id.action_edit).setIcon(R.drawable.ic_launcher);
return true;//返回true表示action mode會被創建 false if entering this mode should be aborted.
}
//
@Override
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
return false;
}
//當ActionMode被點擊時調用
@Override
public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
switch (item.getItemId()) {
case R.id.action_edit:
rename();
return true;
}
return false;
}
//Called when an action mode is about to be exited and destroyed.
//當ActionMode退出銷毀時調用
@Override
public void onDestroyActionMode(ActionMode mode) {
}
};
2、調用startActionMode或者startSupportActionMode開啟彈出框
ActionMode mActionMode = = startSupportActionMode(actionModeCallback)
可以為ActionMode設置屬性：mActionMode.setTitle、mActionMode.setSubtitle
2、使用ActionMode遇到的坑
坑一：ActionMode把Toolbar壓下去了
ActionMode Toolbar
在theme加入配置：
<item name="windowActionModeOverlay">true</item>
<item name="android:windowActionModeOverlay">true</item>
坑二：修改ActionMode背景
在theme加入配置：
<item name="android:actionModeBackground">@color/colorPrimary</item>
<item name="actionModeBackground">@color/colorPrimary</item>
坑三：屏蔽掉WebView的ActionMode用自己的選擇復制
通過js與webView互調來實現文本復制
stackoverflow鏈接：http://stackoverflow.com/questions/6058843/android-how-to-select-texts-from-webview
public class MyCustomWebView extends WebView{
private Context context;
// override all other constructor to avoid crash
public MyCustomWebView(Context context) {
super(context);
this.context = context;
WebSettings webviewSettings = getSettings();
webviewSettings.setJavaScriptEnabled(true);
// add JavaScript interface for copy
addJavascriptInterface(new WebAppInterface(context), "JSInterface");
}
// setting custom action bar
private ActionMode mActionMode;
private ActionMode.Callback mSelectActionModeCallback;
private GestureDetector mDetector;
// this will over ride the default action bar on long press
@Override
public ActionMode startActionMode(ActionMode.Callback callback) {
ViewParent parent = getParent();
if (parent == null) {
return null;
}
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.KITKAT) {
String name = callback.getClass().toString();
if (name.contains("SelectActionModeCallback")) {
mSelectActionModeCallback = callback;
mDetector = new GestureDetector(context,
new CustomGestureListener());
}
}
CustomActionModeCallback mActionModeCallback = new CustomActionModeCallback();
return parent.startActionModeForChild(this, mActionModeCallback);
}
private class CustomActionModeCallback implements ActionMode.Callback {
@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
mActionMode = mode;
MenuInflater inflater = mode.getMenuInflater();
inflater.inflate(R.menu.menu, menu);
return true;
}
@Override
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
return false;
}
@Override
public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
switch (item.getItemId()) {
case R.id.copy:
getSelectedData();
mode.finish();
return true;
case R.id.share:
mode.finish();
return true;
default:
mode.finish();
return false;
}
}
@Override
public void onDestroyActionMode(ActionMode mode) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
clearFocus();
}else{
if (mSelectActionModeCallback != null) {
mSelectActionModeCallback.onDestroyActionMode(mode);
}
mActionMode = null;
}
}
}
private void getSelectedData(){
String js= "(function getSelectedText() {"+
"var txt;"+
"if (window.getSelection) {"+
"txt = window.getSelection().toString();"+
"} else if (window.document.getSelection) {"+
"txt = window.document.getSelection().toString();"+
"} else if (window.document.selection) {"+
"txt = window.document.selection.createRange().text;"+
"}"+
"JSInterface.getText(txt);"+
"})()";
// calling the js function
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
evaluateJavascript("javascript:"+js, null);
}else{
loadUrl("javascript:"+js);
}
}
private class CustomGestureListener extends GestureDetector.SimpleOnGestureListener {
@Override
public boolean onSingleTapUp(MotionEvent e) {
if (mActionMode != null) {
mActionMode.finish();
return true;
}
return false;
}
}
@Override
public boolean onTouchEvent(MotionEvent event) {
// Send the event to our gesture detector
// If it is implemented, there will be a return value
if(mDetector !=null)
mDetector.onTouchEvent(event);
// If the detected gesture is unimplemented, send it to the superclass
return super.onTouchEvent(event);
}
public class WebAppInterface {
Context mContext;
WebAppInterface(Context c) {
mContext = c;
}
@JavascriptInterface
public void getText(String text) {
// put selected text into clipdata
ClipboardManager clipboard = (ClipboardManager)
mContext.getSystemService(Context.CLIPBOARD_SERVICE);
ClipData clip = ClipData.newPlainText("simple text",text);
clipboard.setPrimaryClip(clip);
// gives the toast for selected text
Toast.makeText(mContext, text, Toast.LENGTH_SHORT).show();
}
}
}
menu.xml:
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="@+id/copy"
android:icon="@android:drawable/ic_dialog_email"
app:showAsAction="always"
android:title="copy">
</item>
<item
android:id="@+id/share"
android:icon="@android:drawable/ic_dialog_alert"
app:showAsAction="always"
android:title="share">
</item>
</menu>
坑四：ActionMode顯示時狀態欄閃動，表現為變黑之后恢復正常
在onDestroyActionMode方法加入如下代碼：
@Override
public final void onDestroyActionMode(ActionMode mode) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
new Handler().postDelayed(new Runnable() {
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
@Override
public void run() {
try {
mActivity.getWindow().setStatusBarColor(mActivity.getResources().getColor(android.R.color.transparent));
}
catch(Exception e)
{
e.printStackTrace();
}
}
}, 400);
}
//TODO ...
}
