Laravel 关系中的记录数

Question

]I am beginner php developer. I have project in Laravel 5.6.

I have 2 migrations:

class CreateStopwatches extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('stopwatches', function (Blueprint $table) {
            $table->increments('id');
            $table->integer('case_id')->unsigned();
            $table->foreign('case_id')->references('id')->on('case_instances')->onDelete('cascade');
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('stopwatches');
    }
}



class CreateStopwatchTimeCycles extends Migration
{
    /**
     * Run the migrations.
     *
     * @return void
     */
    public function up()
    {
        Schema::create('stopwatch_time_cycles', function (Blueprint $table) {
            $table->increments('id');
            $table->morphs('timecycle');
            $table->boolean('status')->default(0);
            $table->integer('worked_time')->default(0);
            $table->timestamps();
        });
    }

    /**
     * Reverse the migrations.
     *
     * @return void
     */
    public function down()
    {
        Schema::dropIfExists('stopwatch_time_cycles');
    }
}

And models:

class Stopwatch extends Model
{

    protected $fillable = [
        'case_id'
    ];

    protected $casts = [
        'id' => 'int',
        'case_id' => 'int',
    ];

    protected $dates = [
        'created_at',
        'updated_at'
    ];

    public function timeCycle()
    {
        return $this->morphMany(StopWatchTimeCycle::class, 'timecycle');
    }

}

class StopwatchTimeCycle extends Model
{

    protected $fillable = [
        'case_id'
    ];

    protected $casts = [
        'id' => 'int',
        'case_id' => 'int',
    ];

    protected $dates = [
        'created_at',
        'updated_at'
    ];

    public function stopwatch()
    {
        return $this->morphTo();
    }

}

In my controller I need return 1 - when stopwatches has stopwatches_time_cycles. I make this controller:

public function checkActivity(int $caseId)
    {   
        if (Stopwatch::with(['timeCycle'])->where('case_id', $caseId)->withCount('timeCycle')->first() === 0) {
            return 0;
        } else {
            return 1;
        }
    }

but it's not working correctly. It's always return 1 (I have empty table stopwatch_time_cycles).

How can I repair it?

Please help me

Answer 1

You are comparing your whole StopWatch object to zero, in your first if statement. That's what's causing the error here.

You should save the stopwatch in one variable:

$stopwatch = Stopwatch::with(['timeCycle'])->where('case_id', $caseId)->withCount('timeCycle')->first();

And then, to do your check, if timeCycles exist, you can just do:

if($stopwatch->timeCycle->count() == 0){
...
} else {...}