安卓实战：记事本应用开发

记事本app
package com.example.biji; import android.content.Context; import android.content.DialogInterface; import android.content.Intent; import android.content.SharedPreferences; import android.database.sqlite.SQLiteDatabase; import android.graphics.Color; import android.graphics.drawable.ColorDrawable; import android.media.Image; import android.os.Bundle; import android.preference.PreferenceManager; import android.util.DisplayMetrics; import android.util.Log; import android.view.Gravity; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import android.view.WindowManager; import android.widget.AdapterView; import android.widget.ImageView; import android.widget.ListView; import android.widget.PopupWindow; import android.widget.RelativeLayout; import android.widget.TextView; import androidx.appcompat.app.AlertDialog; import androidx.appcompat.widget.SearchView; import androidx.appcompat.widget.Toolbar; import com.google.android.material.floatingactionbutton.FloatingActionButton; import com.test.greendaodemo.NoteDao; import java.util.ArrayList; import java.util.List; public class MainActivity extends BaseActivity implements AdapterView.OnItemClickListener { //NoteDao mNoteDao = MyApplication.getInstances().getDaoSession().getNoteDao(); private NoteDatabase dbHelper; private Context context = this; final String TAG = "tag"; FloatingActionButton btn; private ListView lv; private NoteAdapter adapter; private List<Note> noteList = new ArrayList<Note>(); private Toolbar myToolbar; private NoteDao noteDao; public NoteDao getNoteDao() { return noteDao; } //弹出菜单 private PopupWindow popupWindow; private PopupWindow popupCover; private ViewGroup customView; private ViewGroup coverView; private LayoutInflater layoutInflater; private RelativeLayout main; private WindowManager wm; private DisplayMetrics metrics; private TextView setting_text; private ImageView setting_image; @Override protected void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initPrefs(); btn = (FloatingActionButton) findViewById(R.id.fab); lv = (ListView) findViewById(R.id.lv); myToolbar = findViewById(R.id.myToolbar); adapter = new NoteAdapter(getApplicationContext(), noteList); refreshListView(); lv.setAdapter(adapter); setSupportActionBar(myToolbar); getSupportActionBar().setHomeButtonEnabled(true); getSupportActionBar().setDisplayHomeAsUpEnabled(true); //设置toolbar取代actionbar initPopUpView(); myToolbar.setNavigationIcon(R.drawable.ic_menu_black_24dp); myToolbar.setNavigationOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Log.d(TAG, "onClick: menu"); showPopUpView(); } }); lv.setOnItemClickListener(this); btn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent intent = new Intent(MainActivity.this, EditActivity.class); intent.putExtra("mode", 4); startActivityForResult(intent, 0); } }); } public void initPopUpView(){ layoutInflater = (LayoutInflater) MainActivity.this.getSystemService(Context.LAYOUT_INFLATER_SERVICE); customView = (ViewGroup) layoutInflater.inflate(R.layout.setting_layout, null); coverView = (ViewGroup) layoutInflater.inflate(R.layout.setting_cover, null); main = findViewById(R.id.main_layout); wm = getWindowManager(); metrics = new DisplayMetrics(); wm.getDefaultDisplay().getMetrics(metrics); } public void showPopUpView(){ int width = metrics.widthPixels; int height = metrics.heightPixels; popupCover = new PopupWindow(coverView, width, height, false); popupWindow = new PopupWindow(customView, (int) (width * 0.67), height, true); popupWindow.setBackgroundDrawable(new ColorDrawable(Color.WHITE)); //在主界面加载成功之后 显示弹出 findViewById(R.id.main_layout).post(new Runnable() { @Override public void run() { popupCover.showAtLocation(main, Gravity.NO_GRAVITY, 0, 0); popupWindow.showAtLocation(main, Gravity.NO_GRAVITY, 0, 0); setting_image = customView.findViewById(R.id.setting_settings_image); setting_text = customView.findViewById(R.id.setting_settings_text); setting_image.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { startActivity(new Intent(MainActivity.this, UserSettingsActivity.class)); } }); setting_text.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { startActivity(new Intent(MainActivity.this, UserSettingsActivity.class)); } }); coverView.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { popupWindow.dismiss(); return true; } }); popupWindow.setOnDismissListener(new PopupWindow.OnDismissListener() { @Override public void onDismiss() { popupCover.dismiss(); Log.d(TAG, "onDismiss: test"); } }); } }); } public void initPrefs(){ SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(getBaseContext()); SharedPreferences.Editor editor = sharedPreferences.edit(); if (!sharedPreferences.contains("nightMode")) { editor.putBoolean("nightMode", false); editor.commit(); } } // 接受startActivityForResult的结果 @Override protected void onActivityResult(int requestCode, int resultCode, Intent data){ int returnMode; long note_Id; returnMode = data.getExtras().getInt("mode", -1); note_Id = data.getExtras().getLong("id", 0); if (returnMode == 1) { //update current note String content = data.getExtras().getString("content"); String time = data.getExtras().getString("time"); int tag = data.getExtras().getInt("tag", 1); Note newNote = new Note(content, time, tag); newNote.setId(note_Id); CRUD op = new CRUD(context); op.open(); op.updateNote(newNote); op.close(); } else if (returnMode == 0) { // create new note String content = data.getExtras().getString("content"); String time = data.getExtras().getString("time"); int tag = data.getExtras().getInt("tag", 1); Note newNote = new Note(content, time, tag); CRUD op = new CRUD(context); op.open(); op.addNote(newNote); op.close(); } else if (returnMode == 2) { // delete Note curNote = new Note(); curNote.setId(note_Id); CRUD op = new CRUD(context); op.open(); op.removeNote(curNote); op.close(); } else{ } refreshListView(); super.onActivityResult(requestCode, resultCode, data); } @Override public boolean onCreateOptionsMenu(Menu menu) { getMenuInflater().inflate(R.menu.main_menu, menu); //search setting MenuItem mSearch = menu.findItem(R.id.action_search); SearchView mSearchView = (SearchView) mSearch.getActionView(); mSearchView.setQueryHint("Search"); mSearchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() { @Override public boolean onQueryTextSubmit(String query) { return false; } @Override public boolean onQueryTextChange(String newText) { adapter.getFilter().filter(newText); return false; } }); return super.onCreateOptionsMenu(menu); } @Override public boolean onOptionsItemSelected(MenuItem item){ switch (item.getItemId()){ case R.id.menu_clear: new AlertDialog.Builder(MainActivity.this) .setMessage("删除全部吗？") .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { dbHelper = new NoteDatabase(context); SQLiteDatabase db = dbHelper.getWritableDatabase(); db.delete("notes", null, null); db.execSQL("update sqlite_sequence set seq=0 where name='notes'"); refreshListView(); } }).setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { dialog.dismiss(); } }).create().show(); break; } return super.onOptionsItemSelected(item); } public void refreshListView(){ CRUD op = new CRUD(context); op.open(); // set adapter if (noteList.size() > 0) noteList.clear(); noteList.addAll(op.getAllNotes()); op.close(); adapter.notifyDataSetChanged(); } @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { switch (parent.getId()) { case R.id.lv: Note curNote = (Note) parent.getItemAtPosition(position); Intent intent = new Intent(MainActivity.this, EditActivity.class); intent.putExtra("content", curNote.getContent()); intent.putExtra("id", curNote.getId()); intent.putExtra("time", curNote.getTime()); intent.putExtra("mode", 3); // MODE of 'click to edit' intent.putExtra("tag", curNote.getTag()); startActivityForResult(intent, 1); //collect data from edit Log.d(TAG, "onItemClick: " position); break; } }}