Battery App Source Code

---------------------------
File: BatteryView.java
---------------------------

package com.skovmandsit.batteryapp;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.content.LocalBroadcastManager;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

public class BatteryView extends Activity {

    private BatteryReceiver batteryReceiver;
    private IntentFilter intentFilter = new IntentFilter(Intent.ACTION_BATTERY_CHANGED);
    public TextView txChargeState, txInformationAge, txPercentCharged;

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

        txChargeState = (TextView) findViewById(R.id.chargeState);
        txInformationAge = (TextView) findViewById(R.id.informationAge);
        txPercentCharged = (TextView) findViewById(R.id.percentCharged);

        // Create the battery receiver
        batteryReceiver = new BatteryReceiver();
        batteryReceiver.setupTextViews(txChargeState,txInformationAge,txPercentCharged);

    }

    @Override
    protected void onResume() {
        super.onResume();

        // Register the broadcastreceiver for the battery status:
        if (batteryReceiver != null) {
            registerReceiver(batteryReceiver, intentFilter);
        }


    }

    @Override
    protected void onPause() {
        super.onPause();

        // Register the broadcastreceiver here:
        if (batteryReceiver != null) {
            unregisterReceiver(batteryReceiver);
        }

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.battery_view, menu);
        return true;
    }

    public void updateTextFields() {
        txChargeState.setText( batteryReceiver.getChargeStateString() );
        txPercentCharged.setText( batteryReceiver.getCurrentCharge() + "%" );
        txInformationAge.setText( batteryReceiver.getInformationFreshnessString() );
    }
}




---------------------------
File: BatteryReceiver.java
---------------------------


package com.skovmandsit.batteryapp;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.os.BatteryManager;
import android.support.v4.content.LocalBroadcastManager;
import android.widget.TextView;


public class BatteryReceiver extends BroadcastReceiver {

    protected enum batteryStates { CHARGING, DISCHARGING, FULL, UNKNOWN }
    protected enum powerSources { WIRELESS, AC, USB, UNKNOWN }

    protected batteryStates currentBatteryState = batteryStates.UNKNOWN;
    protected powerSources currentPowerSource = powerSources.UNKNOWN;

    protected boolean informationIsFresh = false;

    protected int currentCharge = 0;

    public TextView txChargeState, txInformationAge, txPercentCharged;

    public void setupTextViews(TextView mTxChargeState, TextView mTxInformationAge, TextView mTxPercentCharged) {
        txChargeState = mTxChargeState;
        txInformationAge = mTxInformationAge;
        txPercentCharged = mTxPercentCharged;
    }


    @Override
    public void onReceive(Context context, Intent intent) {

        // Get battery level and power source ...
        currentBatteryState = returnBatteryState(intent.getIntExtra(BatteryManager.EXTRA_STATUS, -1));
        currentPowerSource = returnPowerSource(intent.getIntExtra(BatteryManager.EXTRA_PLUGGED, -1));

        // Get information age ...
        if (isInitialStickyBroadcast()) {
            informationIsFresh = false;
        } else {
            informationIsFresh = true;
        }

        // Get current charge ...
        currentCharge = returnCurrentCharge(intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1), intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1));


        txChargeState.setText( getChargeStateString() );
        txPercentCharged.setText( getCurrentCharge() + "%" );
        txInformationAge.setText( getInformationFreshnessString() );

    }

    // Private methods:

    private int returnCurrentCharge(int level, int scale) {

        return (int) ((level / (float)scale) * 100);
    }

    private batteryStates returnBatteryState(int batteryState) {

        switch (batteryState) {
                case BatteryManager.BATTERY_STATUS_CHARGING:
                    return batteryStates.CHARGING;
                case BatteryManager.BATTERY_STATUS_DISCHARGING:
                    return batteryStates.DISCHARGING;
                case BatteryManager.BATTERY_STATUS_FULL:
                    return batteryStates.FULL;
                default:
                    return batteryStates.UNKNOWN;
        }

    }

    private powerSources returnPowerSource(int powerSource) {

        switch (powerSource) {
            case BatteryManager.BATTERY_PLUGGED_USB:
                return powerSources.USB;
            case BatteryManager.BATTERY_PLUGGED_AC:
                return powerSources.AC;
            case BatteryManager.BATTERY_PLUGGED_WIRELESS:
                return powerSources.WIRELESS;
            default:
                return powerSources.UNKNOWN;
        }

    }


    // Public methods / Interface:

    public String getChargingMethod() {
        // Should all be of a kind that says "Charging using: ...."

        switch (currentPowerSource) {
            case USB:
                return "USB";
            case AC:
                return "AC outlet";
            case WIRELESS:
                return "wireless charger";
            default:
                return "unknown method";
        }

    }

    public String getBatteryState() {
        // Should all be of a kind that says "Battery is: ...."

        return currentBatteryState.toString().toLowerCase();
    }

    public String getChargeStateString() {

        switch (currentBatteryState) {
            case CHARGING:
                return "Battery is charging using " + getChargingMethod();
            case DISCHARGING:
                return "Battery is discharging";
            case FULL:
                return "Battery is full";
            default:
                return "Battery and charge state unknown";
        }

    }

    public String getInformationFreshnessString() {
        if (informationIsFresh)
            return "Information is fresh.";
        else
            return "Information is from before the app started";
    }

    public int getCurrentCharge() {
        return currentCharge;
    }
}