实现撤回按钮

src/Notes1/app/src/main/java/net/micode/notes/ui/DrawActivity.java

@@ -1,5 +1,7 @@
 package net.micode.notes.ui;
 
+import static net.micode.notes.tool.DataUtils.TAG;
+
 import android.app.Activity;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
@@ -8,6 +10,7 @@ import android.graphics.Matrix;
 import android.graphics.Paint;
 import android.os.Bundle;
 import android.os.Environment;
+import android.util.Log;
 import android.view.MotionEvent;
 import android.view.View;
 import android.widget.Button;
@@ -102,6 +105,7 @@ public class DrawActivity extends Activity {
         File file = new File(Environment.getExternalStorageDirectory(),
                 System.currentTimeMillis() + ".jpg");
         OutputStream stream;
+        Log.i(TAG, Environment.getExternalStorageDirectory().toString());
         try {
             stream = new FileOutputStream(file);
             mBitmap.compress(Bitmap.CompressFormat.JPEG, 200, stream);

src/Notes1/app/src/main/java/net/micode/notes/ui/NoteEditActivity.java

@@ -38,9 +38,11 @@ import android.location.LocationListener;
 import android.location.LocationManager;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
+import android.text.Editable;
 import android.text.Spannable;
 import android.text.SpannableString;
 import android.text.TextUtils;
+import android.text.TextWatcher;
 import android.text.format.DateUtils;
 import android.text.style.BackgroundColorSpan;
 import android.util.Log;
@@ -69,6 +71,8 @@ import android.speech.tts.TextToSpeech.OnInitListener;
 import net.micode.notes.R;
 import net.micode.notes.data.Notes;
 import net.micode.notes.data.Notes.TextNote;
+import net.micode.notes.gtask.data.Task;
+import net.micode.notes.gtask.data.TaskList;
 import net.micode.notes.model.WorkingNote;
 import net.micode.notes.model.WorkingNote.NoteSettingChangedListener;
 import net.micode.notes.tool.DataUtils;
@@ -88,6 +92,8 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Stack;
+import java.util.Vector;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -111,6 +117,8 @@ public class NoteEditActivity extends Activity implements OnClickListener,
         public ImageView startDraw;
 
         public ImageButton note_Read;
+
+        public Button note_revote;
     }
 
     private static final Map<Integer, Integer> sBgSelectorBtnsMap = new HashMap<Integer, Integer>();
@@ -163,12 +171,16 @@ public class NoteEditActivity extends Activity implements OnClickListener,
 
     private EditText mNoteEditor;
 
+    private Vector<SpannableString> mHistory = new Vector<SpannableString>(10);
+
     private View mNoteEditorPanel;
 
     //private final static int REQUEST_CODE_NEW_NODE  = 103;
 
     private WorkingNote mWorkingNote;
 
+    private boolean mIsRevort;
+
     private SharedPreferences mSharedPrefs;
     private int mFontSizeId;
 
@@ -411,6 +423,13 @@ public class NoteEditActivity extends Activity implements OnClickListener,
         mNoteHeaderHolder.ibSetBgColor = (ImageView) findViewById(R.id.btn_set_bg_color);
         mNoteHeaderHolder.startDraw = (ImageButton) findViewById(R.id.imageButton2);
         mNoteHeaderHolder.note_Read = (ImageButton) findViewById(R.id.menu_note_read);
+        mNoteHeaderHolder.note_revote = (Button) findViewById(R.id.action_undo);
+        mNoteHeaderHolder.note_revote.setOnClickListener(new OnClickListener() {
+            @Override
+            public void onClick(View view) {
+                backTrack();
+            }
+        });
         mNoteHeaderHolder.note_Read.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View view) {
@@ -432,6 +451,26 @@ public class NoteEditActivity extends Activity implements OnClickListener,
         });
 
         mNoteEditor = (EditText) findViewById(R.id.note_edit_view);
+        mNoteEditor.addTextChangedListener(new TextWatcher() {
+            @Override
+            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
+
+            }
+
+            @Override
+            public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
+
+            }
+
+            @Override
+            public void afterTextChanged(Editable editable) {
+                if (!mIsRevort){
+                    saveHistory();
+                }else{
+                    mIsRevort = false;
+                }
+            }
+        });
         mNoteEditorPanel = findViewById(R.id.sv_note_edit);
         mNoteBgColorSelector = findViewById(R.id.note_bg_color_selector);
         for (int id : sBgSelectorBtnsMap.keySet()) {
@@ -482,6 +521,33 @@ public class NoteEditActivity extends Activity implements OnClickListener,
         clearSettingState();
     }
 
+    private void saveHistory(){
+        SpannableString input_text = new SpannableString(mNoteEditor.getText());
+        if (mHistory.size() >= 10){
+            mHistory.removeElementAt(0);
+            mHistory.add(input_text);
+        }else{
+            mHistory.add(input_text);
+        }
+        mNoteHeaderHolder.note_revote.setEnabled(true);
+    }
+
+    private void backTrack(){
+        int stack_size = mHistory.size();
+        mIsRevort = true;
+        if (stack_size <= 1){
+            mNoteHeaderHolder.note_revote.setEnabled(false);
+            return;
+        }else{
+            mNoteEditor.setText((CharSequence) mHistory.elementAt(stack_size - 2));
+            mHistory.removeElementAt(stack_size - 1);
+            if (stack_size == 2){
+                mNoteHeaderHolder.note_revote.setEnabled(false);
+            }
+        }
+
+    }
+
     private void updateWidget() {
         Intent intent = new Intent(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
         if (mWorkingNote.getWidgetType() == Notes.TYPE_WIDGET_2X) {

src/Notes1/app/src/main/res/layout/note_edit.xml

@@ -41,6 +41,13 @@
                 android:layout_weight="1"
                 android:textAppearance="@style/TextAppearanceSecondaryItem" />
 
+            <Button
+                android:id="@+id/action_undo"
+                android:layout_width="wrap_content"
+                android:layout_height="match_parent"
+                android:layout_weight="1"
+                android:text="Button" />
+
             <ImageButton
                 android:id="@+id/menu_note_read"
                 android:layout_width="40dp"