Dialer

An Android app for making phone calls with customized UI, device optimization and multilingual support.

General Structure

The project was made by 3 parts:

• .xml UI design
• Back end Java logic
• Manifest file & other meta data

.xml UI Design

The portrait and view, button labels are beautified by spannableString

The landscape view

The UI was built by nested LinearLayout, scales are vary for different screen sizes

Back End Java Logic

Check if the app has CALL ACTION promission, if not ask the user to give promission and the following operations

private void askForCallPermission() {
        ActivityCompat.requestPermissions(MainActivity.this,
                new String[] {Manifest.permission.CALL_PHONE},
                CALL_PERMISSION_REQUEST_CODE);
    }

@Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions,
                                           int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);

        if (grantResults.length > 0 &&
                grantResults[0] == PackageManager.PERMISSION_GRANTED) {
            makeCall();
        } else {
            makeToast("Allow the permission to make call!");
        }
    }

Clipboard feature to allow user copy the entered number for future process

private void copyToClipboard() {
        ClipboardManager cb = (ClipboardManager) getSystemService(Context.CLIPBOARD_SERVICE);
        ClipData clip = ClipData.newPlainText("number",dialNumber.getText().toString());
        cb.setPrimaryClip(clip);
        makeToast("Number copied to clipboard!");
    }

Button components initialization

btn0.setOnClickListener(l -> addNumber("0"));
btn1.setOnClickListener(l -> addNumber("1"));

Button beautification, where button object will be passed as parameter

private void formatBtn(Button btn) {
        String btnLabel = btn.getText().toString();
        //StyleSpan bss = new StyleSpan(Typeface.BOLD);
        SpannableString ss = new SpannableString(btnLabel);
        AbsoluteSizeSpan ass = new AbsoluteSizeSpan(20,true);
        AbsoluteSizeSpan assAfter = new AbsoluteSizeSpan(10,true);
        ss.setSpan(ass,0,1, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
        //ss.setSpan(bss,0,1, Spanned.SPAN_INCLUSIVE_EXCLUSIVE);
        ss.setSpan(assAfter,1,btnLabel.length(), Spanned.SPAN_INCLUSIVE_INCLUSIVE);
        btn.setText(ss);
    }

Screen modification to hide the top action bar for more spaces

if (this.getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
            requestWindowFeature(Window.FEATURE_NO_TITLE);
            this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
            getSupportActionBar().hide();
        }

Manifest File & Other Meta Data

Some basic information about the app and icon setting

<application
        android:allowBackup="true"
        android:dataExtractionRules="@xml/data_extraction_rules"
        android:fullBackupContent="@xml/backup_rules"
        android:icon="@mipmap/ic_icon"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_icon_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.Dialer"
        tools:targetApi="31">
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

Multilingual support

Use variables for each string

<string name="app_name">Dialer</string>
<string name="call">Call</string>
<string name="del">Del</string>
<string name="copy">Copy Number</string>

The supported languages: English, German, Russian and Spanish

The language of the app will change as the system settings change