Android~檔案存盤案例

1、檔案存盤案例

public class TestActivity extends AppCompatActivity {
    private EditText mFileEdit;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_test);
        initView();
    }

    private void initView() {
        mFileEdit = findViewById(R.id.fileEdit);
        String inputText = load();
        if (!TextUtils.isEmpty(inputText)) {
            mFileEdit.setText(inputText);
            mFileEdit.setSelection(inputText.length());
            Toast.makeText(this, "Restoring succeeded", Toast.LENGTH_SHORT).show();
        }
    }


    @Override
    protected void onDestroy() {
        super.onDestroy();
        String inputText = mFileEdit.getText().toString();
        save(inputText);
    }

    //    從檔案中讀取資料
    public void save(String inputText) {
        FileOutputStream outputStream = null;
        BufferedWriter writer = null;
        try {
            outputStream = openFileOutput("data", Context.MODE_PRIVATE);
            writer = new BufferedWriter(new OutputStreamWriter(outputStream));
            writer.write(inputText);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (writer != null) {
                    writer.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    //    將檔案存盤到檔案中
    public String load() {
        FileInputStream inputStream = null;
        BufferedReader reader = null;
        StringBuilder builder = new StringBuilder();
        try {
            inputStream = openFileInput("data");
            reader = new BufferedReader(new InputStreamReader(inputStream));
            String line = "";
            while ((line = reader.readLine()) != null) {
                builder.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return builder.toString();
    }
}

運行結果，Pass
2、SharePreferences存盤案例

public class SharePfsActivity extends AppCompatActivity implements View.OnClickListener {
    private static final String TAG = "SharePfsActivity";
    private Button mSharedData;
    private Button mRestoreData;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_shared_pfs);
        initView();
    }

    private void initView() {
        mSharedData = findViewById(R.id.sharedBtn);
        mSharedData.setOnClickListener(this);
        mRestoreData = findViewById(R.id.restoreBtn);
        mRestoreData.setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.sharedBtn:
                sharedData();
                break;
            case R.id.restoreBtn:
                restoreData();
                break;
            default:
                break;
        }
    }

    private void sharedData() {
        SharedPreferences.Editor editor = getSharedPreferences("shareData", MODE_PRIVATE).edit();
        editor.putString("name", "功勛");
        editor.putString("type", "電影");
        editor.apply();
    }

    private void restoreData() {
        SharedPreferences preferences = getSharedPreferences("shareData", MODE_PRIVATE);
        String name = preferences.getString("name", "");
        String type = preferences.getString("type", "");
        Log.d(TAG, "名稱：" + name + "，型別：" + type);
    }
}

運行結果，Pass